Item No. 1 of 34

INVESTIGATOR: Barnes, P.

PERFORMING INSTITUTION:
AGRI ENGINEERING
KANSAS STATE UNIV
MANHATTAN, KANSAS 66506

DEVELOPMENT AND EVALUATION OF TMDL PLANNING AND ASSESSMENT TOOLS AND PROCESSES

OBJECTIVES: 1.Develop, improve, and evaluate watershed models and other approaches for TMDL development and implementation. 3.Assess the potential ecological benefits/implications of TMDL implementation at watershed level.

APPROACH: Kansas State University has developed an extended watershed monitoring program to access the parameters needed to quantify Kansas's water quality total maximum daily loads TMDLs. The monitoring is also used to identify the source of the contaminants. With this spatial and temporal information, best management practices are developed to reduce these TMDL impairments. The cost of monitoring and state wide testing of best management practices require that available data be used to calibrate models that can predict the impact of practices on TMDL water quality issues in other areas of Kansas. Only two of Kansas's twelve major watershed basins have been monitored with enough sufficiency to address TMDL issues. Properly calibrated TMDL models can help predict parameters needed to address water quality issues in watersheds with limited data.

NON-TECHNICAL SUMMARY: The Clean Water Act requires States to monitor their water and its ability to meet intended uses If the water exceed quality standards, then the State is required to set goals to reduce these contaminants This project will examine the source of these contaminants and implementation of practices that will reduce their presence to meet water quality standards.

PROJECT CONTACT:

Name: Barnes, P.
Phone: 785-532-291
Fax: 785-532-5825
Email: 1barnes@ksu.edu

Item No. 2 of 34

INVESTIGATOR: Schmidt, J.; Rice, C.

PERFORMING INSTITUTION:
AGRONOMY
KANSAS STATE UNIV
MANHATTAN, KANSAS 66506

ASSESSING NITROGEN MINERALIZATION AND OTHER DIAGNOSTIC CRITERIA TO REFINE NITROGEN RATES FOR CROPS AND MINIMIZE LOSSES

OBJECTIVES: 1. Develop and evaluate rapid tests for soil N mineralization capacity across the various soils and climatic regimes of the region and determine the feasibility and most appropriate conditions for use of theses tests. 2.Conduct fundamental work to enhance current understanding of the role of active C and N pools in cropping systems and to predict net N mineralization as influenced by C sequestration management. 3. Develop a guideance document for agricultural professionals focusing on N best management practices and optimum rate determinations for the region.

APPROACH: A common field experimental design and a centralized analytical laboratory approach will be used to accomplish the stated objectives. Project participants will select new or appropriate existing experimental locations within their states. Each site will have at least five N rates (including a no N control) bracketing the range of the anticipated optimum N rate for the experimental location and will contain at least four replications. Corn grain yield will be measured in each plot at the end of the growing season. This will allow identification of the economic optimum N rate and construction of a model describing N response at each site. These response functions can be used to project the consequences of applying reduced N rates (below economic optimum) on crop production levels and the risk of N loss to the environment. The amount of excess N applied at rates above the observed optimum can be used to evaluate the relationships between excess N and potential nitrate losses. This will allow estimation of the consequences of reducing N inputs on the potential for N loss and on crop productivity. Dr. Richard Mulvaney at the University of Illinois will perform tests for N mineralization potential by amino sugar analysis of the soil samples collected at each field site. Preliminary comparisons of soil amino sugar levels with field data on corn N response show a promising relationship between amino sugar levels and the occurrence of yield response to added N. Arrangements for the analyses in Dr. Mulvaney's laboratory will be coordinated through Dr. Robert Hoeft, who is the official NC-218 representative from the University of Illinois. Potential C and N mineralization assays on soils collected from the field plots will be used to determine the size and turnover rate of active and more resistant soil C and N pools. The potential C and N mineralization data (cumulative mineralization curves) will be fit to an additive exponential model to describe meaningful soil organic matter (SOM) pools and associated turnover rates for C and N. The kinetic analysis of incubation data will be used to relate to mineralizable soil N pools under field conditions. To assess the impact of soil C sequestration management on soil N availability characteristics, the recently deposited plant residue organic matter fraction will be examined. Data from the proposed project and from previous projects conducted by the NC-201 and NC-218 committees will form the database for the guidance document to be prepared as a committee activity. If data from the new project is combined with core experiment results from the previous projects conducted by NC-201 and NC-218, information from about 500 experiments conducted throughout the region will be available to form the research base for the guidance document. A summary of current approaches to N best management practices for corn in the North Central region will be included in the document.

NON-TECHNICAL SUMMARY: This study evaluates the role of active carbon (C) and nitrogen (N) pools in cropping systems that contribute to N mineralization and availability in cropping systems. Improving N use for cropping systems in the North Central Region will be essential to addressing water quality issues such as nitrate enrichment in groundwater and the hypoxia in the Gulf of Mexico.

PROGRESS: 2002/01 TO 2002/12
The current project is a continuation of the previous regional project, so there were some field studies that provided results for this year. Corn was grown at six field sites in 2002. Multiple N rates were applied with different times of application, including 270 and 220 lb N acre-1 applied pre-plant, 220 lb N acre-1 (1/2 applied pre-plant, 1/2 applied when corn was knee high), 165 lb N acre-1 (1/3 applied pre-plant, 2/3 applied when corn was knee high), 110 lb N acre-1 (1/5 applied pre-plant, 2/5 applied when corn was knee high, 2/5 applied when corn was waist high), and zero N applied. At every site, 165 lb N acre-1 was sufficient to achieve maximum yield for the previous two growing seasons. This is considerably less than current Kansas State University recommendations of 200 ? 230 lb N acre-1. This is probably a result of the two applications (pre-plant and as the corn is growing) as opposed to one application pre-plant, resulting in more efficient N use. Water samples collected throughout the growing season from the 4-ft depth indicates that less nitrate was reaching this depth when N is applied in a split application compared to when the entire N was applied at planting. In another study, the N supplying capacity of the soil was evaluated after 10 years of manure and fertilizer application and after 5 years of N application followed by 5 years with no additional N inputs. Corn yields were not significantly different between tillage treatments or among N sources when applied at similar N rates. No-tillage (NT) and manure (M) significantly increased soil organic C and N. Six yr after N application were discontinued, total N uptake from N mineralization represented about 81 and 66 kg N/ha for M and fertilizer (F), respectively. In situ N mineralized from planting to tasseling at 0- to 30-cm depth accounted for 38 and 22% of N uptake from M and F, respectively. Predicted and actual N mineralization in situ was highly correlated (r =0.82, p = 0.0001).

IMPACT: 2002/01 TO 2002/12
Reducing N rates by 50 lb N acre-1, without a risk of reduced yield, will save Kansas corn producers about $10 acre-1 in production costs. This translates to $30,000,000 for about 3,000,000 acres of corn planted annually in Kansas. This also translates into lower nitrate in the groundwater below agricultural fields, providing environmental benefits to the Kansas public. Nitrogen mineralization can supply a substantial protion of the N supply for a corn crop. Up to 80 kg N/ha could be supplied from this souil which represented 2% of the total soil N. Quantifying N mineralization and plant uptake is essential to minimizing risk associated with excess N applications and reducing input costs.

PUBLICATIONS: 2002/01 TO 2002/12
1. Scharf, P.C., J.P. Schmidt, N.R. Kitchen, K.A. Sudduth, S.Y. Hong, J.A. Lory, and J.G. Davis. 2002. Remote Sensing for Nitrogen Management. J. Soil Water Conserv. 57:In Press.
2. Schmidt, J.P., A.J. DeJoia, R.B. Ferguson, R.K. Taylor, R. K. Young, and J.L. Havlin. 2002. Corn Yield Response to Nitrogen at Multiple In-Field Locations. Agron. J. 94:798-806.
3. R.J. Gehl, J.P. Schmidt, L.R. Stone, L.D. Maddux, and W.B. Gordon. 2002. Nitrate Leaching Characteristics for Various Nitrogen Management Strategies on Irrigated Corn. In Proceedings of the 32nd North Central Extension - Industry Soil Fertility Conference, Des Moines, IA. 20-21 November, 2001.
4. Gehl, R.J., J.P. Schmidt, G.A. Clark, A.J. Schlegel, and L.R. Stone. 2002. Evaluating Nitrate Leaching Characteristics for Various Nitrogen Mangement Strategies on Irrigated Corn along the Lower Arkansas River, Kansas. In Annual Meeting Abstracts, (CD-ROM computer file S04-gehl1165635-oral) ASA-CSSA-SSSA. 10-14 Nov. 2002. Indianapolis, IN.
5. Gehl, K.A, and C.W. Rice. 2002. Tillage and fertilizer placement effects on N distribution in soil, runoff, and plants. In Annual Meeting Abstracts, (CD-ROM computer file S03-gehl101916-oral) ASA-CSSA-SSSA. 10-14 Nov. 2002. Indianapolis, IN.
6. Mikha, M.M., and C.W. Rice. 2002. Aggregate C and N as affected by tillage and manure. In Annual Meeting Abstracts, (CD-ROM computer file S03-mikha152742-poster) ASA-CSSA-SSSA. 10-14 Nov. 2002. Indianapolis, IN.

PROJECT CONTACT:

Name: Schmidt, J.
Phone: 785-532-7211
Fax: 785-532-6094
Email: jschmidt@bear.agron.ksu.edu

Item No. 3 of 34

INVESTIGATOR: Clark, G. A.; Alam, M.; Fjell, D.; Martin, V. L.; Rogers, D. H.; Trooien, T. P.; Vanderlip, R.; Gordon, B.; Ham, J.; Hamilton, S.; Lamm, F.; Schlegel, A.

PERFORMING INSTITUTION:
AGRI ENGINEERING
KANSAS STATE UNIV
MANHATTAN, KANSAS 66506

WATER CONSERVATION AND MANAGEMENT IN CROP SYSTEMS

OBJECTIVES: 1. Develop, evaluate, and promote irrigation and cropping system designs, technology, and management practices for efficient water and chemical use in crop production systems. A. Develop and field test subsurface drip irrigation (SDI) system design and management guidelines for use with agronomic field crops in Kansas. B. Evaluate center pivot irrigation system nozzle package components, designs, and installations for uniform and efficient application of water. C. Educate irrigation system managers and crop consultants on how to access and use automated weather station data and historic weather data to estimate crop water use. D. Develop and evaluate crop cultural, crop management, and irrigation water management practices for efficient water use and optimal production. 2. Design and implement strategies for the application and management of urban, industrial, and agricultural wastewater resources with irrigation systems to: A. Evaluate irrigation system components and designs for use with wastewater resources. B. Evaluate wastewater as an irrigation resource for use in cropping systems.

APPROACH: #1.Field studies using SDI systems for field crop production will be conducted to evaluate irrigation system design and management techniques. #2.Laboratory studies of tubing hydraulic & chemical solution distribution characteristics will be conducted to evaluate drip irrigation product designs and management strategies. #3.Irrigation system managers/operators will be educated on how to access weather data, how to incorporate that data into a water management program, and then how to use that information for irrigation scheduling and water management.#4.Irrigation scheduling & management programs will be observed at nine farmer cooperator fields. The information will be provided to the farmers to help them develop and implement improved management procedures. #5.BMPs will be developed & demonstrated for using solid animal waste from confined beef and swine operations. The study will help develop proper usage procedures of the waste for agricultural production & provide information on the environmental benefits and impacts on water quality. #6.This project is designed to examine the interactions of major cultural practices on continuous corn grain yields on the sandy soils of the lower Arkansas River Basin. Special attention is given to the effects of planting date, tillage & hybrid maturity on grain yield as effected by irrigation rate. #7. Nitrogen fertilizer will be applied with variable-rate application equipment, based on yield goals & analyses of grid based soil samples. Irrigation applications will be managed by the producer/cooperator & applied as uniformly as possible using a standard center pivot system so that measured water use is a function of yield goal and resultant applied fertility. #8.Field evaluations of full sized center pivot irrigation systems using catch cans will be conducted to assess irrigation uniformity. After identification of non-uniform packages, additional investigations of non-uniform irrigation packages will be conducted to assess installation and/or design problems. #9.This project involves testing various sprinkler package options for use when irrigating with low-capacity wells. Sprinkler test options will include low-pressure in-canopy (LPIC) nozzles in either spray or bubble mode & 360-degree spray nozzles. #11.This research will include laboratory & field studies designed to assess sprinkler irrigation system design & uniformity of water applications. Laboratory Studies:Sprinkler water distribution patterns will be measured from various combinations of orifice size, operating pressure, and deflector plates; Individual nozzle pattern data will be used in a simulation model to evaluate various device spacing, discharge, and pressure combinations. Obj.2., #2.Various field and system tests will be conducted to evaluate system design & management parameters related to the use and management of SDI with treated wastewater. #10.The lagoon water is filtered with a disk filter and an automatic backflush controller. Chlorine (household bleach) and acid (N-pHuric 15-49) are injected for system maintenance and cleaning. Drip tubing flow rates and crop yield are used as indicators to evaluate system performance.

NON-TECHNICAL SUMMARY: Develop, evaluate, and promote irrigation and cropping system designs, technology, and management practices for efficient water and chemical use in crop production systems.

PROGRESS: 2002/01 TO 2002/12
Objective 1. (A). Lab studies conducted on the evaluation of drip tape products at elevated water temperatures showed that the relationship between emitter discharge rate and water temperature was different for different manufacturers and product wall thickness. (B) Field studies were conducted to evaluate the performance of catch collectors with different size openings under fixed-plate, grooved disk sprinklers and rotating plate sprinklers. Catch collectors need to have openings of at least 15 cm in diameter with fixed-plate, grooved disk sprinkler packages, while 10 cm diameter openings are acceptable for evaluation of rotating plate sprinklers. Center pivot irrigation system uniformity testing and field day events were conducted on five sites with a total attendance of 42 people. (C) The KanSched irrigation scheduling program was written into a Visual Basic code and further refined for use as a simple evapotranspiration-based irrigation scheduling tool. Several "Online" electronic tools (programs) were developed to help irrigation system managers, crop consultants and others with water management, cropping systems and energy use decisions. Those tools are displayed on the MIL website at http://www/oznet/ksu.edu/mil/. (D) Completed the 2nd year of a limited irrigation cropping systems study. Profitability was greatest with soybean (as compared with corn, sorghum, or sunflower) and increased with applied irrigation. Objective 2. A field site to evaluate drip emitter performance with livestock lagoon wastewater was completed and operated through the 2002 summer. The entire site was seeded to alfalfa and established in 2002. Part of that site was redesigned to evaluate the effect of supplemental compost and lagoon wastewater on alfalfa production and nutrient removal. Livestock lagoon wastewater was analyzed for various constituents to determine potential treatment recommendations for use with drip irrigation systems. Lab studies with soil cells were initiated on the effects of using chlorine treated or untreated lagoon wastewater on soil N and P concentrations and bacterial populations. Technology Transfer. A "Limited Irrigation Field Day" was held at Tribune with the topics of: Limited irrigated, no-till cropping systems drainage considerations in irrigation management, timing of last irrigation in corn, water and manure management, and the Mobile Irrigation Lab. A Field Day at Garden City showed manure application field research, percolation lysimeters, and had a Mobile Irrigation Lab demonstration. Eleven KanSched computer training sessions were held (220 people) and eight Mobile Irrigation Lab (MIL) orientation and seminar sessions (695 people) were held. Audiences included irrigated crop producers, crop consultants, county agents, and water agency representatives (NRCS, Water Office, Conservation Districts, etc.). The MIL website (http://www/oznet/ksu.edu/mil/) has been maintained and enhanced with a larger photo gallery, software instruction manuals (with print and audio files), and "Online" software tools.

IMPACT: 2002/01 TO 2002/12
Drip irrigation designers, installers, and operators will be more aware of system benefits, design and operational constraints, and system management for general crop production with SDI and to apply lagoon waste water resources through SDI systems. Irrigated crop producers have more tools (KanSched, Online Tools, the IrriGage) and data to help with irrigation system selection and scheduling decisions. Livestock waste research will provide information for improved management practices and to minimize non-beneficial leaching of nutrients associated with land application of liquid waste products.

PUBLICATIONS: 2002/01 TO 2002/12
1. Alam, M., T. P. Trooien, T. J. Dumler, and D. H. Rogers. 2002. Using Subsurface Drip Irrigation for Alfalfa. Journal of the American Water Resources Association. Vol.38, No.6, 1-7.
2. Alam, M., T. P. Trooien, D. H. Rogers, and T. J. Dumler. 2002. An Efficient Irrigation Technology for Alfalfa Growers. Journal of Extension. Vol. 40, No.3, 1-9.
3. Alam, M., D. H. Rogers, T. J. Dumler, and G. L. Gold. 2002. Effect of Irrigation Ending Date on Corn Yield and Irrigation Scheduling for Water Conservation. In Proc. ASAE Annual International Meeting/CIGR XVth World Congress, July 28-31, 2002, at Chicago. Paper No. 022062. Available from ASAE, St. Joseph, MI 49085.
4. Clark, G. A., D. H. Rogers, E. Dogan, and R. Krueger. 2002. The Irrigage: A Non-Evaporating In-Field Precipitation Gage. Paper No. 022068 presented at the 2002 ASAE International Meeting, Chicago. 9p.
5. Rogers, D. H., G. Clark, M. Alam, D. L. Fjell, and R. Stratton. 2002. A Mobile Irrigation Lab (MIL): Bringing education and technical assistance to the farm in the computer age. Paper No. 022021 presented at the 2002 ASAE International Meeting, Chicago. Dogan, E., G. A. Clark, D. H. Rogers, and V. L. Martin. 2002. Systematic sprinkler nonuniformity effect on corn yield at south central Kansas. Paper No. 022061 presented at the 2002 ASAE International Meeting, Chicago. 23p.
6. Clark, G., D. Rogers, M. Alam, D. Fjell and S. Briggeman. 2002. A Mobile Irrigation Lab For Water Conservation: I. Physical and Electronic Tools. Presented at the 2002 Irrigation Association (IA) Technical Conference and Trade Show, New Orleans. 8p. Rogers, D. H., G. Clark, M. Alam, R. Stratton, and S. Briggeman. 2002. A Mobile Irrigation Lab For Water Conservation: II Educational Programs and Field Data. Presented at the 2002 Irrigation Association (IA) Technical Conference and Trade Show, New Orleans. 8p.
7. Lamm, F. R., Todd P. Trooien, Gary A. Clark, Loyd R. Stone, Mahbub Alam, Danny H. Rogers, and Alan J. Schlegel. 2002. Using Beef Lagoon Wastewater with SDI . Presented at the 2002 Irrigation Association (IA) Technical Conference and Trade Show, New Orleans. 8p.

PROJECT CONTACT:

Name: Clark, G. A.
Phone: 785-532-5580
Fax: 785-532-5825
Email: gclark@bae.ksu.edu

Item No. 4 of 34

INVESTIGATOR: Taylor, R.; Schmidt, J.; Creager, B.; Dhuyvetter, K.; Dille, A.; Kastens, T.; Kilgore, G.; Kluitenberg, G.; Lamond, R.; Maddux, L.; Schlegel, A.; Schrock, M.

PERFORMING INSTITUTION:
AGRI ENGINEERING
KANSAS STATE UNIV
MANHATTAN, KANSAS 66506

PRECISION AGRICULTURE TECHNOLOGIES

OBJECTIVES: Determine the biological and ecological mechanisms responsible for the spatial distribution of weed populations in crop production fields and apply this understanding of temporal and spatial weed distributions on a small scale in building field level weed scouting and management programs. Assess the spatial variability of soil physical properties and relate to yield. Quantify NO3 leaching potential in the irrigated sands along Kansas' waterways under current and alternative N and water management strategies for corn. Evaluate yield response to alternative N and water management practices for irrigated corn production. Incorporate study results into improved N recommendations from Kansas State University. Develop improved P fertilizer recommendations for the major crops in Kansas by evaluating the implications of managing soil test P with the goal of achieving the greatest return given a specific time horizon for land tenure. Evaluate grain yield response to increased soil test P and increased P fertilizer. Characterize the spatial variability in soil test phosphorus (P) for typical Kansas's soils. Characterize the stability of soil test P for repeated soil sampling throughout the year. Develop algorithms for spatial application of herbicide inputs. Researchers plan to assist with commercialization of multi-point pulse-width modulation for NH3 metering and distribution. Evaluate the effectiveness of application systems and associated technologies to improve spray quality through increased efficacy and reduced drift. To design a direct-contact soil dielectric-permitivity sensor capable of simultaneously measuring at least two soil properties: water content and salt content and test the sensor and its calibration model for the sensor in laboratory and fields.

APPROACH: A combination of small plots, transects, and field scale research will be used to evaluate spatial variability and crop responses to inputs. Small plots and field scale research will be used to evaluate crop responses while transects and field scale research will be used to determine spatial variability of soils, weed populations, and yield. Transects have been selected at two experiment fields for analysis of velvetleaf seedling emergence and control strategies. A transect on a cooperator's field was selected for evaluation of the effects of soil physical properties on corn yield. To quantify NO3 leaching potential, treatments will be imposed using a factorial treatment design at three fields along the Lower Arkansas River (sandy-textured soils), two Experiment Fields, and one small-plot and field-scale site at Manhattan. Two irrigation schedules will be used at one field, optimal and 25% greater than optimal and one irrigation schedule will be used at all other locations. Six nitrogen fertilizer treatments will be established at all fields and replicated four times. Individual plots will be 8 rows wide and 30 ft long with grain yield determined by hand-harvesting two middle rows. The flow capacity and lateral distribution of prototype manifold/cooler will be evaluated. Water absorption will be used to capture the NH3 delivered by the outlet tubes. Each water absorption bucket is suspended from a load cell, and the weight of the bucket, water, and NH3 is logged in real time by a computerized data acquisition system. A linear regression will then be performed on the weight vs. time data to determine the mass flow rate of NH3 from each outlet. Spray efficacy and drift will be evaluated for emerging sprayer technologies through field plot research. Droplet-scanning software will be used to measure spray droplet characteristics on water sensitive paper collected during in-field applications of crop protection products to assess spray coverage and drift potential. Prototype permitivity sensors will be laboratory tested with different plate sizes, shapes, separations, and materials at different frequency ranges in order to find the optimum design parameters. Tests will also be conducted to determine the minimum penetration depth. These sensors will be made to 1/8-scale and evaluated at ranges of soil moisture, salinity, and clay contents. The field-scale prototype sensor will be a scaled-up design of the sensor developed during the laboratory test. However, the scale-up will not be a simple proportional enlargement, because the penetration depth of the sensor in field will need to be reduced to avoid excessive disturbance to the soil.

NON-TECHNICAL SUMMARY: All of these technologies focus on improving the efficiency with which resources such as fertilizer, soil amendments, and pesticides are used.

PROGRESS: 2002/01 TO 2002/12
Researchers developed and evaluated new equipment and sensors to improve application of agricultural inputs. Researchers completed the redesign of a real-time, weed-detection/spray control system. The redesign was aimed at a modular design approach using a higher-layer CAN protocol and the IEEE-1451 "smart transducer" concept. They also further tested a soil permittivity sensor, which was designed to simultaneously measure multiple soil physical properties. Research was conducted to evaluate application efficacy and droplet characteristics of crop protection application equipment. Spray tip type and application volumes and pressures were compared for new and existing herbicides using a ground sprayer. Insecticide application coverage and canopy penetration were assessed in soybeans using aerial and ground sprayers and in sunflower using aerially application. Researchers worked toward the commercialization of a multi-point pulse width modulation metering and distribution system for NH3. Two manifold casting revisions were made to improve valve sealing and serviceability. Durability tests were performed by pumping liquid NH3 through the valves at a pressure drop of about 40 psig. A twelve-valve system was operated at 15 Hz for a total of 3.2 million cycles per valve. No failures occurred and disassembly of the valves revealed no abnormal wear or deposits. Research was conducted to evaluate optimal seeding rate for corn by planting strips at different seeding rates in fields with varying soil type to determine the affect of soil type and environmental factors affect corn emergence and corn yields. The economic feasibility of reducing preemergence herbicide use for corn was evaluated. A uniform rate of atrazine was applied on a field with varying soil properties and weed populations. Three rates of premixed flufenacet and isoxaflutole were applied in repeated strips across the field. Individual weed species were identified and mapped at 2,176 grid points, then uniformly sprayed with postemergence mixture of prosulfuron + primisulfuron and diflufenzopyr. Weeds were remapped at the original grid points after 6 weeks. A 2/3 rate of flufenacet and isoxaflutole resulted in maximum economic return. Four field sites were identified with cooperating farmers and one field site was established at the Kansas River Valley (KRV) Experiment Field to improve P management strategies. Georeferenced soil samples were collected at each site. Yield was measured at all sites with combines equipped with yield monitors and DGPS. Corn was grown at six field sites with multiple N rates and application timing. Grain yield results for two growing seasons indicate that 165 lbs N per acre was sufficient to achieve maximum yield though producers typically apply more than 200 lbs N per acre while achieving similar yield. At one location, 110 lbs N per acre in three split applications was sufficient to maximize yield in a limited irrigation treatment but not with greater water application. Post-harvest soil samples collected to 8 ft indicated that nitrate-N was leaching to below the 5-ft depth at N rates greater than 165 lb N per acre and for the higher irrigation treatment.

IMPACT: 2002/01 TO 2002/12
Results from the P fertilizer project will be used to improve recommendations, which will improve the economic return for all Kansas' producers. Fertilizer recommendations will include a method for optimizing economic return to P fertilizer assuming some length of land tenure (this has never before been available). Reducing N rates by 50 lb N per acre, without risking yield loss, will save Kansas corn growers about $10 per acre in production costs. This translates to $30,000,000 for the 3,000,000 acres of corn planted annually in Kansas. Quantifying this affect for producers will be essential to minimizing the risk (nitrate-N leaching to groundwater) associated with excess N applications. The NH3 application system has the potential to improve the accuracy of NH3 application and allow users to more closely meet the fertility needs specific field areas. The PWM system will enable producers to address point rows and other partial-width applications and is also capable of very rapid changes in application rate. The crop protection application equipment research will help applicators to make better decisions regarding herbicide and insecticide application parameters. Spatial variability in weed populations and potential impact on crop yield makes it possible to reduce preemergence herbicide rates and still achieve adequate control. The 2/3X rate across variable soils and weed populations was the optimal rate. Given the potential benefits of variable application and the value of measuring weed populations, the weed sensor research could have the potential for commercialization.

PUBLICATIONS: 2002/01 TO 2002/12
1. Kastens, T.L., J.P. Schmidt, and K.C. Dhuyvetter. "Yield Response Implied by Fertilizer Recommendations." Paper was presented by Kastens and published in the proceedings of the 2002 Great Plains Soil Fertility Conference, Denver, Colorado, March 5-6, 2002. pp 53-60.
2. Nivens, H., T. Kastens, K. Dhuyvetter, and A. Featherstone. "Using Satellite Imagery in Predicting Kansas Farm Land Values." Journal of Agricultural and Resource Economics. 27,2:(December 2002):464-480.
3. Zhang, N., M. Wang, and N. Wang. 2002. Precision Agriculture - a Worldwide Overview. Computers and Electronics in Agriculture. Elsevier Press. 36 (2002) 113-132.
4. Wang, M. and N. Zhang. 2002. Information technology alters the roadmap to agricultural modernization. Guest Editorial, Computers and Electronics in Agriculture. Elsevier Press. 36 (2002) 91-92
5. Wang, N., N. Zhang, J. Wei, Q. Stoll, D. Peterson, and F. Dowell. 2002. Wheat field tests for an optical sensor-based, real-time, embedded, weed-detection and spray-control system. ASAE Paper No. 02-1179, American Society of Agricultural Engineers, St. Joseph, MI.
6. Wei, J., N. Zhang, N. Wang, D. Lenhert, M. Neilsen, M. Mizuno, and G. Singh. 2002. A structural and modular approach to implement communication interface for tractor electronics communication using CAN Kingdom. ASAE Paper No. 02-1178, American Society of Agricultural Engineers, St. Joseph, MI.
7. Rider, T.W. and J.A. Dille. 2002. Economic evaluation of reducing preemergence herbicides for site specific weed management. Proc., North Central Weed Science Society, St. Louis, MO. Abstract #26.

PROJECT CONTACT:

Name: Taylor, R.
Phone: 785-532-2931
Fax: 785-532-5825
Email: rtaylor@bae.ksu.edu

Item No. 5 of 34

INVESTIGATOR: Heer, W.; Janke, R.; Havlin, J.

PERFORMING INSTITUTION:
AGRONOMY
KANSAS STATE UNIV
MANHATTAN, KANSAS 66506

LEGUMES AS A NITROGEN SOURCE IN NO-TILL ROTATIONS FOR SOUTH CENTRAL KANSAS

OBJECTIVES: 1)Determine to what extent Legume cover crops add Carbon and Nitrogen to the soil in a wheat-legume-grain sorghum cropping sys- tem under no-till practices. 2) Determine the water use efficiency and ground cover effects of the legume in the cropping system. 3) Evaluate the effects of legume cover crops on the yield and quality of the grain harvested from the following sorghum crop.

APPROACH: A randomized complete block design with six treatments will be used. The six treatments, three nitrogen rates (0, 56, and 112 Killograms nitrogen per hectare) and three legumes (hairy Vetch, Sweet Clover, and winter peas) will follow the wheat and preceed the grain sorghum in the rotation. Prior to seeding each crop soil samples to a depth of one meter will be taken. These samples will be used to determine the effect of the previous crop/fertilizer had on soil N and OM. Random plants will be removed from the legume plots and evaluated for nodulation of the bacteria with the host plant. Plant biomass data will be collected at maturity for each crop. Uniform plot areas will be harvested to determine grain yield, quality and N content. Soil water content will be determined at planting and harvest. Precipitation, air temperature, humidity, solar radiation, and wind speed will be monitored near the plots. Supplemental data on water infiltration rate, bulk density, microbial respiration and water filled pore space will be collected to support the above data. All data collected will be analyzed using the appropriate statistical procedure to determine the significance of the effect of the legume on the crop and soil parameters outlined.

PROGRESS: 1995/10 TO 2000/09
The 2000 grain sorghum harvest was the harvest that represented the completion of one complete cycle of this rotation. The winter pea, hairy vetch, and sweet clover plots were planted in mid-September(1999)and terminated in mid-April of2000. Fall and Spring growth of the legumes was similar to the first two years and not as good as 1999. Ground cover and biomass production for the hairy vetch and winter peas was considered good only in 1999. In mid January 1999 both had 62 percent ground cover with above ground biomass productions of 4431 and 3338 kg ha-1 respectively. This equates to 162 and 112 kg ha-1 nitrogen from the hairy vetch and winter peas respectively. Nitrogen attributed to the legumes in 2000 was 36 and 14 kg ha-1 respectively. This is very similar to the first two years of the research. As in previous years, grain sorghum yields showed no advantage to the use of a cover crop over that of commercial fertilizer. In 1999 when biomass N was high grain sorghum yields showed that the total biomass N was apparently not available to the sorghum. Analysis for seed nitrogen(percent)in the sorghum showed the same effect for the cover crop treatments when compared to the N fertilizer treatments. Grain moisture at harvest and grain test weight were not significantly affected by treatment. Results for the winter wheat following grain sorghum in the rotation for the first two cycles indicated significant difference for only the 0-N treatment. In 2000 where the rotation had completed a cycle and the soil system began to show the rotational effects the wheat yields for the legume treatments were significantly lower that the two fertilizer treatments. The sweet clover treatments never contributed sufficient dry matter and therefore no N credit for this treatment was realized over the term of the study.

IMPACT: 1995/10 TO 2000/09
Impact In years when weather favors growth of cover crops large amounts of N can be produced. This N does not necessarily result in increased yields in the following crop. Rotations need to be carried out over an extended period of time to determine the effects of the rotation and what is occurring as a result of previous soil characteristics. The data from 2000 indicate cover crop N takes considerable time under no-till conditions to be detected in the succeeding crop yields.

PUBLICATIONS: 1995/10 TO 2000/09
No publications reported this period

Item No. 6 of 34

INVESTIGATOR: Janssen, K.; Whitney, D.

PERFORMING INSTITUTION:
AGRONOMY
KANSAS STATE UNIV
MANHATTAN, KANSAS 66506

EFFECTS OF LONG-TERM CROP RESIDUE REMOVAL AND FERTILIZER APPLICATION ON SOIL AND CROP YIELD

OBJECTIVES: The purpose of this study is to determine the long-term effects of returning different quantities of crop residue on soil properties and crop yield in a soybean-wheat-corn rotation, fertilized with different amounts of N-P-K fertilizer.

APPROACH: Existing residue/fertility treatments at the East Central KS Experiment Field will be used for this study. The residue treatments which were begun in 1980 are (i) crop residue removed after grain harvest each year, (ii) normal crop residue incorporated, and (iii) twice normal (2X) crop residue incorporated (accomplished by spreading evenly the residue from the residue removal treatments). Also included are fertilizer treatments which are superimposed over the residue treatments at zero, low, normal, and high levels of N-P-K fertilizer. Effects of the residue and fertilizer treatments will be evaluating using a wheat-soybean-corn rotation with grain and residue yields measured each year. Soil samples will be taken at the beginning and end of the study to measure treatment effects on soil chemical and physical properties.

PROGRESS: 1995/10 TO 2000/09
Research was conducted during 1995 to 2000 to measure the 15-19 year effects of harvesting and return of varying levels of crop residues on crop yield and soil properties in a soybean-wheat-grain sorghum/corn rotation, fertilized with different levels of N, P, and K fertilizer. The residue treatments caused no differences (0.05 level) in grain yields during any year. Grain yields, averaged across all crops, fertilizer treatments, and years, were 2924 kg/ha with annual residue harvesting, 2938 kg/ha with normal residue incorporated, and 2802 kg/ha with 2X normal residue incorporated. The fertilizer treatments (zero, low, normal and high levels of (N, P, and K) produced significant yield differences. Five year, average grain yields ranged from 2131 kg/ha at the zero fertilizer rate to 3570 kg/ha at the highest level of fertilizer. Soil samples collected showed that soil organic matter and soil exchangeable K declined with crop residue harvesting.

IMPACT: 1995/10 TO 2000/09
The harvesting of crop residues appears to be not that detrimental to crop production over the short-term on soils having initially good fertility and organic matter levels. However, harvesting of crop residues continuously remains questionable as a sustainable practice. It lowers soil organic matter and depletes soil nutrients, especially K. The effects of these slowly developing changes in soil properties on crop yields needs further study.

PUBLICATIONS: 1995/10 TO 2000/09
Janssen, K.A. and D.A. Whitney 2000. Crop residue removal and fertilizer effects on crop yield and soil sustainability. In D. Fjell (ed.) Field Research 2000, Kansas Agric. Exp. Sta. and Coop. Ext. Ser. Rep.of Progress 854, May 2000.

Item No. 7 of 34

INVESTIGATOR: Pierzynski, G. M.; Thien, S. J.; Rice, C. W.

PERFORMING INSTITUTION:
AGRONOMY
KANSAS STATE UNIV
MANHATTAN, KANSAS 66506

PLANT NUTRIENT CYCLING IN SOILS

OBJECTIVES: The objectives are to evaluate several methods for assessing soil P bioavailability, to evaluate the losses of N in relation to plant productivity, and to evaluate N fertilizer management in conservation tillage cropping systems.

APPROACH: Soil samples of varying P bioavailabilities will be obtained from field experiments and evaluated for P bioavailability with several new methods. One measures the total amount of inorganic P that can be desorbed or dissolved from soil with an Fe oxide sink. The other estimates microbial biomass P. Nitrogen mineralization and immobilization will be assessed under both laboratory and field conditions utilizing incubations and the use of 15N. Denitrification will be measured on intact soil cores collected from field experiments using the acetylene inhibition method. Field studies will be used to study fertilizer management. Varying rates of N applied as urea with or without urease inhibitor will be compared to similar amounts of N applied as ammonium nitrate and to a no N control. Plant tissue composition, chlorophyll meter readings, yields, and soil chemical properties will be measured.

PROGRESS: 1995/10 TO 2000/09
Application of animal manures and biosolids to agricultural land is a common practice for recycling plant nutrients. Excessive soil P levels are a concern because of potential water quality impacts and new nutrient management guidelines require consideration of P. The objectives of this study were to monitor the effects of various P sources on soil test P (STP) levels and soil P fractions in six Kansas soils in a greenhouse study. A modified Hedley's fractionation procedure was employed. Two cattle manures, turkey litter, biosolids, swine waste, and triple superphosphate (TSP) were added at 50 and 150 mg P/kg soil and corn was grown 7 times. The influence of P source on STP varied with the soil prior to cropping, although the turkey litter produced the lowest STP levels across all soils and TSP produced the highest STP levels in four soils. All of the P sources increased inorganic soil P fractions as measured with the fractionation procedure. Treatment effects on soil organic P fractions were variable although none of the C-rich P sources increased organic P substantially. STP levels decreased with cropping. For some soil-P source combinations a curvilinear decrease was found with STP levels reaching a minimum near the initial STP value. For other soil-P source combinations a linear increase in STP was found with separate curves for each level of added P. No-tillage (NT) and conventional tillage (CT), and two N sources (manure and commercial fertilizer) were continuously applied to a Kennebec silt loam (fine silty, mixed, mesic Cumulic Hapludolls) soil (10 years) in North Agronomy Farm, Manhattan, KS. Corn yield was not affected by tillage systems or N source. Denitrification activity was enhanced with manure application. The effect of tillage system and N sources on the amounts and depth distribution of residual NO3-N was investigated. Conventional tillage tended to increase the amount of NO3-N in the profile. Fertilizer resulted in significantly (P<0.05) higher NO3-N at depths below 30 cm in, but no significant difference between manure and fertilizer was found at soil surface (0-15 cm). Therefore, conventional tillage in commercial fertilizer resulted with the higher risk of groundwater contamination. The long-term affect of NT and manure application was the improvement in N supplying capacity of the soil. When N additions were stopped, yields were maintained in the treatments receiving manure. Yields were reduced the year after N fertilizer was stopped and were similar to the no N treatment after the second year.

IMPACT: 1995/10 TO 2000/09
Information obtained from this project has been invaluable in nutrient management planning within the state. Permits for swine facilities require that STP levels not exceed critical values over the 5-year life of the permit. This necessitates predicting STP levels into the future based on the overall P budget for the soil. Data from this project helped verify ratios used to predict changes in STP based on net addition or removal of P from the soil. In the second study, in addition to the improvement in soil organic N, soil C was also improved in that we had a gain of 2 MT C/ha with no-tillage and additional gains when manure were added. Thus the overall soil quality had improved with NT and manure.

PUBLICATIONS: 1995/10 TO 2000/09
1. Shafqat, M. and G.M. Pierzynski. 2000. Phosphorus source and rate effects on soil phosphorus fractions. Agron. Abs. P. 401. Am. Soc. of Agron., Madison, WI.
2. Davis, B., G.M. Pierzynski, F. Vocasek, and L. Freese. 2000. Nutrient management programs in Kansas. Agron. Abs. P. 414. Am. Soc. of Agron., Madison, WI.
3. Pierzynski, G.M. 2000. Phosphorus cycling in agroecosystems: Nutrient management planning. Agron. Abs. P. 246. Am. Soc. of Agron., Madison, WI.

Item No. 8 of 34

INVESTIGATOR: Sweeney, D. W.

PERFORMING INSTITUTION:
KSU SE AGRICULTURE RES CENTER
KANSAS STATE UNIV
MANHATTAN, KANSAS 66506

SOIL AND WATER MANAGEMENT FOR CROP PRODUCTION IN SOUTHEASTERN KANSAS

OBJECTIVES: 24. OBJECTIVES: To determine optimum soil and water management practices for crop production in southeastern Kansas by: 1) evaluating soil fertility and tillage management practices and cropping sequences necessary for optimum production in southeastern Kansas; 2) determining the feasibility of limited- amount supplemental irrigation as affected by cultural practices to maximize crop production and quality.

APPROACH: 25. APPROACH: Individual field studies will be established at the KSU Southeast Agricultural Research Center and at other locations in southeastern Kansas (as necessary) to compare soil fertility management practices, tillage systems, water management practices (including irrigation), and other soil and water management practices. Relevant plant and soil measurements will be taken and compared. Test crops will include grain sorghum, corn, soybeans, grasses, and popcorn.

PROGRESS: 1995/10 TO 2000/09
I: In a long-term grain sorghum-soybean rotation, sorghum yields tend to be lower with no-tillage. Conventional and reduced tillage have resulted in similar yields during the study. Adding nitrogen (N) in any form has increased long-term average grain sorghum yields by 60 percent. Sorghum yield response to the different N managements has varied with year, but anhydrous ammonia has increased average yields by about 6 bu/a above urea and 8 bu/a over urea-ammonium nitrate solution. Soybean yields tend to be unaffected by tillage. II: Short-season corn yields tend to be little affected by phosphorus stratification in soil. III. Early results suggest that seed production from endophyte-free fescue tends to be greater from late-fall N fertilization than late-winter. In contrast, timing of N application may be less important for the residual forage left after seed harvest. However, especially when applied in late winter, subsurface N placement resulted in greater after-seed-harvest forage than when N was surface broadcast. IV: Although the response varies with year, wheat yield can be affected by timing of nitrogen or phosphorus and potassium fertilization. However, subsequent double crop soybean yield was less influenced.

IMPACT: 1995/10 TO 2000/09
On low to moderately productive soils typical of southeastern Kansas, information on optimum fertilizer placement, timing, and rates maximize yields and economic returns and reduce potential hazards to the environment.

PUBLICATIONS: 1995/10 TO 2000/09
1. Sweeney, D.W. 2000. Soil fertility research - Southeast Agricultural Research Center. p. 42-50. In: 1999 Kansas Fertilizer Research Report of Progress 847.
2. Sweeney, D.W. 2000. Soil and water management research. p. 32-41. In: Kansas Agr. Exp. Station Report of Progress 853.
3. Sweeney, D.W., Granade, G.V., Eversmeyer, M.G., and Whitney, D.A. 2000. Phosphorus, potassium, chloride, and fungicide effects on wheat yield and leaf rust severity. J. Plant Nutr. 23:1267-1281.
4. Sweeney, D.W., and Moyer, J.L. 2001. Sulfur source and placement for newly established endophyte-free tall fescue. Commun. Soil Sci. Plant Anal. 32:(in press).

Item No. 9 of 34

INVESTIGATOR: Thompson, C. A.

PERFORMING INSTITUTION:
KSU AGRICULTURE RES CTR-HAYS
KANSAS STATE UNIV
MANHATTAN, KANSAS 66506

MANAGEMENT OF SOIL IN DRYLAND REGIONS

OBJECTIVES: 1) Summarize long-term organic matter loading study, continue managing current study to stimulate decomposition of grass and newsprint, and seek new funding for soil analysis in tracking soil fertility changes. 2) Determine yield components of winter wheat, soil nutrient changes, and the economic response as affected by synthetic protein aspartic acid (PAA). 3) Develop new management techniques that enhance grain and forage production efficiency of traditional and alternate crops.

APPROACH: 1) Timely tillage and planting operations will continue after the November, 1994final waste application in order to track soil nutrient changes to include the C:N ratio. 2) Monitoring the effects of 3 methods of application and 5 rates of PAA, each at 4 levels of nitrogen will be conducted on Ike winter wheat. 3) Conventional and alternate grain and forage crops will be tested under various management systems (tillage systems, fertilizer and variety/hybrid comparisons, planting date, seeding rate and row spacing) to determine their annual effect on yield components and economic return.

PROGRESS: 1995/10 TO 2000/09
CONSERVATION TILLAGE. Over a 30-year period, production of wheat and sorghum was higher with reduced-till than with no-till on level high fertility silt loam soils. No-till did not increase soil organic matter. CROP ROTATIONS. Successfully increasing the intensity of the cropping system was heavily dependent on depth of soil water at planting. Wheat-sorghum-fallow was a low risk rotation. However, continuous sorghum shows promise when depth of soil water was 36-inch or more. FERTILIZING DRYLAND CROPS. Greater efficiency and higher net return was realized when fertilizer was banded with the seed. The main caution was to use modest N rates. Modest levels of surface-applied and incorporated materials had a greater return per dollar invested than larger amounts. AMISORB. This linear polyacrylamide increased yields when banded with the seed. STOCKOSORB. This cross-linked polyacrylamide improved yields when banded with fertilizer in the seed row. The AGRO F formulation could be blended with liquid fertilizer without gelling of the material. This allowed a more uniform application. SMALL GRAIN FORAGE. Over an 8-year period, triticale and rye cultivars are showing great promise in producing high levels of biomass for grazing or hay. Spring triticale varieties with the winter hardiness of Jagger wheat are showing promise because of their photo non-sensitive characteristics.

IMPACT: 1995/10 TO 2000/09
Depth of soil water had the greatest single effect on crop production and net return. Tillage systems should be based on cost-effectiveness. Banding low fertilizer rates provided the highest net return. Applying cross-linked polymers in liquid fertilizer resulted in a synergistic effect on crop production. Grazing small grain forages resulted in greater return per acre than grain production.

PUBLICATIONS: 1995/10 TO 2000/09
1. Thompson, C.A. 1998. Effects of Stockosorb AGRO applications on yields and economic returns of winter wheat and grain sorghum in Central Kansas. KS Fert. Res. 1997. Report of Progress 800, January 1998, pp 34-48.
2. Thompson, C.A. 2000. Effects of the cross-linked polyacrylamide Stockosorb on wheat, triticale, and grain and forage sorghums in Central Kansas. KS Fert. Res. 1999. Report of Progress 847, January 2000, pp 21-35.
3. Thompson, C.A. 2000. Effects of liquid AmiSorb on winter wheat in Central Kansas. KS Fert. Res. 1999. Report of Progress 847, January 2000, pp 36-41.

Item No. 10 of 34

INVESTIGATOR: Schmidt, J. P.

PERFORMING INSTITUTION:
AGRONOMY
KANSAS STATE UNIV
MANHATTAN, KANSAS 66506

ENHANCING NUTRIENT EFFICIENCY FOR WESTERN KANAS

OBJECTIVES: 1. Recalibrate the profile N soil test for dryland winter wheat grown under highresidue management. The calibrations will include the influences of N placement (surface and subsurface placement) and timing (spring and fall). 2. Evaluate the influence of PMN on improving the accuracy of predicting optimum N rate for irrigated and dryland crops. 3. Quantify the fertilizer phosphorus (P) management effects on residual fertilizer P availability and develop an improved fertilizer P recommendation model to include residual fertilizer P availability. 4. Evaluate the production potential of alternative dryland cropping systems for western Kansas.

APPROACH: Both field and laboratory methods will be utilized to address the project objectives. New field studies will be initiated for objectives 1, 3, and 4, while existing field experiments will be used for objective 2. Laboratory experiments also will be conducted for objectives 2 and 3.

PROGRESS: 1995/10 TO 2000/09
Lime and P Study: Soil samples from three fields in south central Kansas were collected on one-acre grids using a systematically unaligned procedure, in 1998, 1999, and 2000. Lime recommendations were determined from the 1998 soil samples and an interpolated spread map was created using the inverse distance squared method. A uniform lime recommendation was determined by averaging the lime recommendations for all soil sample points in a given field. The rate of lime applied was determined for each sample point by averaging all lime-applied values within a 15-m radius around each soil sample point. If the uniform rate of lime had been applied to Fields 1 and 2, 50% of the field would have been misapplied by more than 1120 kg ECC ha-1. Only 23% of Field 3 would have been misapplied by more than 1120 kg ECC ha-1, if a uniform rate had been applied. Comparing the soil pH (2000) to soil pH (1998) for both limed and unlimed areas of the field indicated that those areas of the field receiving lime and were initially lower in soil pH did receive more lime than those areas with initially greater soil pH. This was one measure of success in targeting lime to the appropriate areas of the field. A model was developed that was used to evaluate yield as a function of numerous independent variables. This model indicated that maximum yield was achieved for soil pH equal to 6.1, with yield decreasing slightly when pH deviates in either direction. A site-specific lime application increases the probability of achieving the agronomically desirable soil pH for the greatest percentage of the field. Iron Study: Seven irrigated cornfields in SW Kansas were identified in 1999 and 2000 for Fe deficiency symptoms. A problematic area, known to display Fe chlorosis, within each field was identified. Treatments included four rates of iron sulfate monohydrate (0, 27, 54, and 81 kg product per ha), one rate of CaSO4 (85 kg product per ha), one rate liquid iron sulfate heptahydrate (375 L per ha), and one foliar application of Nortrace HEEDTA chelated Fe replicated four times in a Randomized Complete Block Design. Each plot was four rows wide (76-cm rows) and 10 m long. The iron sulfates and calcium sulfate were placed in the seed slot at planting. The foliar Fe application was applied at about the V4 growth stage. At four sites, grain yield increased with increasing iron sulfate monohydrate application, increasing 2.3 Mg per ha between the control and the 81 kg per ha application. This represents a $4.75 return per $1.00 spent in fertilizer costs. However, at three field sites, the grain yield response to the iron sulfate monohydrate was not significant. Grain yield for other treatments evaluated were not different from the control.

IMPACT: 1995/10 TO 2000/09
Improving grain yield in Fe-deficient soils, representing 10 to 20% of fields in areas of SW Kansas, provided a substantial return per Fe fertilizer costs ($4.75 : $1.00) for 4 of 7 sites evaluated in this study. This level of return can quickly pay for the additional equipment costs associated with geographic information systems (GIS) and global positioning systems (GPS) technologies. A more detailed economic impact for both of these studies is still in progress.

PUBLICATIONS: 1995/10 TO 2000/09
1. Godsey, C.B., J.P. Schmidt, A.J. Schlegel, R.K. Taylor, C.R. Thompson, R.J. Gehl. 2000. Correcting iron deficiency in corn using site-specific iron sulfate applications in the seed row. p. Agronomy Abstracts. ASA, Madison, WI.
2. Olsen, C.J., R.E. Lamond, J.P. Schmidt, and R.K. Taylor. 2000. Correcting soil pH variability with site-specific lime applications for wheat. p. Agronomy Abstracts. ASA, Madison, WI.
3. Olsen, C.J., R.L. Lamond, J.P. Schmidt. 1999. Site-specific lime application to reduce phosphorus loading in Cheney Watershed, Kansas. p. Agronomy Abstracts. ASA, Madison, WI.

Item No. 11 of 34

INVESTIGATOR: Schlegel, A. J.

PERFORMING INSTITUTION:
KSU SW AGRICULTURE RES CENTER
KANSAS STATE UNIV
MANHATTAN, KANSAS 66506

SOIL FERTILITY AND WATER MANAGEMENT FOR WESTERN KANSAS

OBJECTIVES: 1. A. Recalibrate the profile N soil test for dryland winter wheat grown under high residue management. B. Determine the long term effects of fertilization and residue management of irrigated crops on crop production, profitability, and soil quality. C. Determine management practices to efficiently utilize nutrients from manure to optimize producer profitability without degrading soil or water resources. 2. Determine the feasibility of alternative dryland cropping systems with regard to grain production, profitability, water use efficiency, precipitation capture and storage, residue cover, and soil and water quality. 3. Develop methods to efficiently utilize limited amounts of irrigation for optimize crop production and profitability for regions with declining groundwater resources.

APPROACH: Measure crop growth, nutrient uptake, soil chemical properties, and environmental impact from various fertilizer management practices, including time, rate and placement of organic and inorganic nutrient sources. Measure the interaction between tillage, fertility, and crop selection on water and nutrient use efficiency, crop production, soil properties, and sustainability in a semi-arid environment. Quantify crop production potential, water use efficiency and economic feasibility of alternative management systems for utilizing limited amounts of groundwater for irrigation of agricultural crops.

PROGRESS: 1995/10 TO 2000/09
Irrigated corn N and P rates: The economic optimal N rate was about 180 kg per ha averaged across 30 years and was similar in low-, medium- and high-yielding years. Application of N at the economic optimal rate did not cause nitrate accumulation in the soil or leaching below the crop root zone. Application of P increased grain yield by 3750 kg per ha and net revenue by 320 dollars per ha. Animal waste management: A survey was made of fields in western Kansas that had received long-term (up to 30 yr) application of swine or cattle wastes. Soil P levels in the surface soil in most instances were below 200 mg per kg. Some movement of nitrate was detected past the crop root zone but not deeper than 4.5 m (groundwater tables were generally in excess of 30 m). Soil zinc and copper levels were not elevated by application of animal wastes. Dryland cropping systems: Reduced-(RT) and no-tillage (NT) increase precipitation capture and reduce evapotranspiration. A wheat-sorghum-fallow (WSF) rotation increased precipitation use efficiency by 25 percent over a wheat-fallow (WF) system; however, profitability was similar for RT-WF compared to WSF. Green fallow: Growing a legume during the fallow period has potential as a forage crop, but reduced yields of subsequent grain crops too much to be recommended in western Kansas. Cropping systems: Wheat yields vary in 3-yr rotations (wheat-summer crop-fallow) depending on the preceding crop. Averaged across 5-yr, wheat yields were 7 percent lower following corn and 21 percent lower following sunflower compared to wheat following grain sorghum. Dryland tillage systems: Conservation tillage increased grain yields in a WSF rotation. Averaged across ten years, wheat yields were 2550 kg per ha with conventional tillage (CT), 2890 kg per ha with RT, and 3090 kg per ha with NT while grain sorghum yields were 2820 kg per ha with CT, 4390 kg per ha with RT, and 4770 kg per ha with NT. While production costs were higher with conservation tillage, net revenue was 32 dollars per ha greater with RT than CT for wheat and 74 dollars per ha greater with either RT or NT than CT for grain sorghum. Intensive 4-yr cropping systems: Averaged across four years, the second wheat crop in a wheat-wheat-sorghum-fallow rotation yielded 74 percent of the first wheat crop (2890 vs. 3900 kg per ha, respectively). In a wheat-sorghum-sorghum-fallow rotation, averaged across four years, the second sorghum crop yielded 71 percent of the first sorghum crop (4010 vs. 5650 kg per ha, respectively). Although the 4-yr rotations increased total production compared to a 3-yr rotation, the more intensive systems did not increase profitability. Limited irrigation: Grain sorghum yields more than corn at irrigation amounts less than 206 mm, whereas corn yields more than grain sorghum when more than 206 mm of irrigation is available.

IMPACT: 1995/10 TO 2000/09
Grain yields and profitability are increased with application of fertilizer or animal wastes. Applications of these nutrients pose little environmental risk when applied at the economic optimal rate. For dryland crop production, conservation tillage can increase precipitation use efficiency, grain yield, and profitability while making more intensive cropping systems feasible in western Kansas.

PUBLICATIONS: 1995/10 TO 2000/09
Trooien, T.P., F.R. Lamm, L.R. Stone, M. Alam, D.H. Rogers, G.A. Clark, and A.J. Schlegel. 2000. Subsurface drip irrigation using livestock wastewater:dripline flow rates. App. Engr. In Agr. 16(5):505-508.

Item No. 12 of 34

INVESTIGATOR: Janke, R.; Havlin, J.; Kluitenberg, G.

PERFORMING INSTITUTION:
AGRONOMY
KANSAS STATE UNIV
MANHATTAN, KANSAS 66506

A COST/BENEFIT/RISK ANALYSIS OF VARIOUS SOIL IMPROVING PRAC ICES

OBJECTIVES: 1) Conduct field and laboratory tests using selected indicators of soil improvement. 2) Determine if there is a relationship between field history/cropping system management and the selected indicators. 3) Calculate the cost, benefits, and risk of the soil improving practices (reduced tillage, diverse crop rotation, cover crops, manure and compost amendments).

APPROACH: Identify on-going replicated long term trials in Kansas (five years duration or longer). Select treatments within these experiments that contrast soil improving practices with control treatments. Also identify paired fields on commercial farm operations within a soil mapping unit that contrast soil improving management with a control site. Conduct in-field and laboratory measurements to quantify various indicators of soil quality including: water infiltration rate, water holding capacity, bulk density, size classification of water stable aggregates, microbial respiration rate, pH, total carbon, total nitrogen, profile nitrate nitrogen, phosphorus, potassium, cation exchange capacity, and soluble salt content. Use various statistical techniques to determine relationships between cropping system management and the indicators of soil improvement. Partial budget analysis will be used to determine the input costs of various cropping systems and a cost- benefit analysis of the various soil improving practices will be performed.

PROGRESS: 1995/10 TO 1998/09
Results this year show that some of the field-based tests suggested for farmer use are not practical or sensitive enough to recomend in Kansas. Other tests work quite well. The minimum data set of soil quality indicators for Kansas will differ from those in other states, due to the imiportance of water infiltration rate and water holding capacity in a semi-arid climate. New tests developed as simplified versions of lab tests for water stable aggregates and saturated water content were sensitive to changes in soil management, consistent, and repeatable, and will be recommended. Particulate organic matter is a more sensitive test to recent changes in soil quality than total organic matter. Future work will emphasize providing access to these tests to farmers through use of field test kits and commercial labs being able to offer a range of soil physical tests in addition to soil chemical tests.

PUBLICATIONS: 1995/10 TO 1998/09
No publications reported this period

Item No. 13 of 34

INVESTIGATOR: Barnes, P. L.; Slocombe, J. W.; Clark, S. J.

PERFORMING INSTITUTION:
AGRI ENGINEERING
KANSAS STATE UNIV
MANHATTAN, KANSAS 66506

SUSTAINABILITY OF TILLAGE SYSTEMS IN AN IRRIGATED CORN-SOYBEAN CROP ROTATION

OBJECTIVES: 1. Evaluate the sustainability of different tillage systems. 2. Compare energy use efficiencies of different tillage systems. 3. Quantify the levels of compaction under different tillage systems.

APPROACH: Effects of normal and shear loading from track and wheel machinery soil physicalproperties will be analyzed via hydraulic conductivity measurements. A simulation model to predict compaction from machinery will be developed and field tested. Ongoing research plots will be used to compare conventional, conservation, and no-till tillage systems in terms of physical and chemical properties. Observation wells and piezometers will be used to collect groundwater samples from a corn-soybean rotation. Runoff water will be analyzed for nitrate and herbicide concentrations and correlated to crop growth stage and weed counts. Energy inputs for crop production under each tillage system will be studied.

PROGRESS: 1995/10 TO 2000/09
This program has examined a full range of tillage systems to include systems using full, reduced, and no tillage. Full tillage includes some form of residue management, which could include stalk shredding after harvest followed by disking and a deep tillage with a chisel. Residue levels left after this tillage are minimal. During spring preparation for planting, field cultivation is used to incorporate fertilizer and herbicides for weed control. This is a common practice used by 80% of the farmers in Kansas. These practices prevent loss of fertilizer and pesticides to surface runoff in the spring but strong thunderstorms can cause large erosion events before crop canopies cover the soils. Reduced and no till practices leave larger amounts of residue on the soil surface. This residue blanket protects the soil surface from the thunderstorm raindrop energy, which causes soil erosion. During the past ten years we have monitored a large reduction in the sediment loads in our streams and lakes. These reductions in sediment loads in streams can be attributed to reduced tillage and conservation programs. But with this improvement in sediment control we have also seen an increase in pesticides in streams and lakes. With reduced tillage and proper timing of pesticide application, reduction of both sediments and pesticides can be achieved.

IMPACT: 1995/10 TO 2000/09
During the past year Kansas farmers using improved tillage systems have achieved several exciting accomplishments. In the past, most Kansas streams and lakes were reported as impaired by sediments, nutrients, and pesticides according to standards set by the Environmental Protection Agency Clean Water Act. The 1998 Clean Water report showed that pesticides impaired only six reservoirs. With implementation of the new Total Maximum Daily Loading requirements we are finding that the improved sediment loading we had seen in our streams may not be sufficient to meet TMDL requirements. This may require that farmers implement additional conservation and reduced tillage practices to meet these water standards.

PUBLICATIONS: 1995/10 TO 2000/09
No publications reported this period

Item No. 14 of 34

INVESTIGATOR: Davis, L. C.

PERFORMING INSTITUTION:
BIOCHEMISTRY
KANSAS STATE UNIV
MANHATTAN, KANSAS 66506

MUTATIONAL ANALYSIS OF NITROGENASE IRON PROTEIN

OBJECTIVES: I. We will determine the relationship of chemically induced mutational changes of amino acids in the iron protein to alterations in function of nitrogenase from Klebsiella pneumoniae. II. We will introduce site directed mutations of iron protein genes into Klebsiella pneumoniae and determine their effect on nitrogenase function.

APPROACH: DNA sequencing will be used to determine alteration in chemically induced and site-directed mutants of the iron protein. Gel electrophoresis of extracts will be used to monitor status of expressed proteins. By using native reducing gels, in presence of magnesium or ADP we can examine the formation of the iron protein and its influence on formation of the molybdenum iron protein of nitrogenase. Repression by ammonium addition and SDS gel electrophoresis will be used to monitor stability of the mutants. Urea gradient gels will be used to determine the unfolding properties of the iron protein.

PROGRESS: 1996/10 TO 2001/09
We have characterized the phenotypes and genotypes, by DNA sequencing, for 54 chemically induced mutants in the Fe protein of Klebsiella pneumoniae nitrogenase. All of these have the strong phenotype of being unable to grow with dinitrogen as a source of N, but in addition, they show various modifications in ability to synthesize enzymes involved in the production of the MoFe protein of nitrogenase. The crystallographic structure of the protein had been determined elsewhere, and we have been able to attribute specific effects to many of the mutants, which are in some cases unable to bind the hydrolyzable substrate ATP, and in others are unable to produce a correctly folded protein. Some are simply unable to interact effectively with the MoFe protein. Several publications have previously been reported. One is in revision and another in preparation.

IMPACT: 1996/10 TO 2001/09
Biological nitrogen fixation is an energetically costly process which is essential for supply of nitrogen to plants, but which only occurs in bacteria. To understand the process well enough to attempt to engineer it, examination of mutants with defects in the enzyme is an efficient approach. If the enzyme process is fully understood, it may be possible to do engineering to broaden the range of organisms benefiting from it directly. Now the limiting factor in genetic engineering is determining how to protect the enzyme from oxygen inactivation, and how to supply all of the necessary cofactor inputs for synthesis of an effective enzyme in a non-bacterial sytem.

PUBLICATIONS: 1996/10 TO 2001/09
No publications reported this period

Item No. 15 of 34

INVESTIGATOR: Xia, K.; Kalita, P.

PERFORMING INSTITUTION:
AGRONOMY
KANSAS STATE UNIV
MANHATTAN, KANSAS 66506

THE IMPACT OF FERTILIZERS AND HERBICIDES ON WATER QUALITY

OBJECTIVES: Objectives. 1. We will determine the adsorption/desorption and kinetics of adsorption onto soil of atrazine and other important herbicides commonly used in Kansas. 2. The leaching of agricultural chemicals (i.e., nitrate, phosphate, triazines) will be quantified in field situations as affected by soil management by using an existing weighing lysimeter facility.

APPROACH: Approach. The overall goal of this project is to evaluate various agricultural chemicals and soils for potential water contamination. Soils and sites will be selected based upon the properties of the soils and the vulnerability of the underlying aquifer for contamination. Adsorption will be determined using classical batch techniques, and desorption will be measured using soil from adsorption experiments. Kinetics of adsorption will be determined over time periods ranging from 30 minutes to 10 days. The leaching of agricultural chemicals through soil will be approached by using a recently-completed lysimeter facility. Four undisturbed soil cores (2 x 2 x 1.5 m deep) were placed in a central weighing facility. During the next few years, the facility will be fully calibrated, tested, and extensively used in the monitoring of pesticide movement through Kansas soils. The facility will allow us to study transport of herbicides in a field setting while still being able to obtain a complete mass balance of water and solutes. The information received from this project will assist in evaluating management techniques to prevent contamination of ground water and surface water by agricultural chemicals.

PROGRESS: 1996/10 TO 2001/09
A series of weighing lycimeters were developed for use in this project. During the past year this facility was redesigned to enhance precision and calibration and testing done to enhance our capacity to determine accurately the mass balance of nutrient and pesticides moving through soils. A new project will be developed to utilize this valuable facility.

IMPACT: 1996/10 TO 2001/09
Development of a mass balance of nutrients and pesticides is critical to understanding fate and transport in the environment. This facility will be extremly valuable for future efforts.

PUBLICATIONS: 1996/10 TO 2001/09
No publications reported this period

Item No. 16 of 34

INVESTIGATOR: Maddux, L. D.

PERFORMING INSTITUTION:
AGRONOMY
KANSAS STATE UNIV
MANHATTAN, KANSAS 66506

EFFECTS OF APPLICATION METHOD,TIME, AND RATE OF SUPPLMENTAL ON IRRIGATED SOYBEANS

OBJECTIVES: Determine the optimum method, time, and rate of supplemental N application on irrigated soybean leaf N content, plant population, maturity date, plant height, pod number, seed weight, and grain yield.

APPROACH: N rates of 0, 33.6, and 67.2 kg N/a will be applied to irrigated soybeans as UANdribbled at last cultivation and anhydrous ammonia knifed at approximately R1 growth stage (beginning bloom) and as UAN fertigated at R1, R3 (beginning pod), and R5 (beginning seed). Data collected will include leaf N concentration at approximately R6, plant population, maturity date, plant height, pod number, seed weight, and grain yield.

PROGRESS: 1996/10 TO 2000/09
A study was conducted to evaluate nitrogen (N) application time and rate on irrigated soybeans. The dribble UAN and anhydrous ammonia applications did not affect soybean yield. Fertigation at the R3 growth stage resulted in slight yield increases of 2.0 and 3.0 bu/a in 2 of 3 years. Fertigation at R1 and R5 did not affect soybean yield. This research supports the results of previous research conducted in Kansas that indicated that application of supplemental N at pod set could increase soybean yield. The yield increases obtained in thsi study were not as great as that obtained in some of the previous studies. This would indicate that a large response should not be expected every year. However, if a producer is set up to apply N through a sprinkler system, beneficial yield increases could be obtained in some years. Results do seem to vary from field to field, so this practice should be evaluated by producers on a field by field basis.

IMPACT: 1996/10 TO 2000/09
Supplemental applications of N as UAN applied as fertigation treatments to soybeans at R3 growth stage tended to increase soybean yields 2 of the 3 years tested. This would support other Kansas research and give Kansas soybean growers an option of increasing soybean productivity in some years by applying 20-40 lbs N/a at R3.

PUBLICATIONS: 1996/10 TO 2000/09
No publications reported this period

Item No. 17 of 34

INVESTIGATOR: Sunderman, H. D.

PERFORMING INSTITUTION:
KSU NW AGRICULTURE RES CENTER
KANSAS STATE UNIV
MANHATTAN, KANSAS 66506

ALTERNATIVE CROPS AND CROPPING SYSTEMS IN NORTHWESTERN KANSAS

OBJECTIVES: A. Determine the economics and degree to which sunflower yield, quality, and crop residue characteristics can be improved through the manipulation of cultural practices.

APPROACH: Objective 1--Studies on dryland to include sunflower tillage, sunflower row spacing and plant population, and comparison of five summer crops for water use, nutrient uptake, yield, quality, dry matter, and crop residue. Objective 2--Winter canola investigations will continue to evaluate performance of selections and commercially available varieties.

PROGRESS: 1996/10 TO 2000/09
SUMMER CROPS IN A WHEAT-SUMMER CROP-FALLOW ROTATION: Standard corn (StC), dwarf corn (DwC), grain sorghum (GS), pearl millet (PM), and oilseed sunflower (OS) were compared for 3 growing seasons. In dry years, OS removed available soil moisture (ASM) at a faster rate early in the season. The same was observed for OS in a wet season, with StC and DwC being intermediate, and PM and GS the lowest. The 3-yr average crop residue amounts for StC (6.51 Mg/ha), GS (5.99), and PM (6.62) were statistically similar, and all 3 were greater than either DwC (4.40) or OS (4.28). StC produced the greatest amount in a wet year (10.56 Mg/ha) whereas PM (6.17) and GS (5.79) produced the greatest in dry years. Greatest year-to-year variability in grain yield and net return was by DwC, intermediate with StC and PM, and least with OS and GS. Averaged over the 3-yr period, highest net return was from StC and OS. Row spacing and planting date of irrigated soybean: Pioneer 9333 and 9396 were planted in 38- and 76-cm row spacings on 14, 21, 28 May and 5, 11, 18 June. Overall, yields averaged 3.19 Mg/ha with the lowest (2.75 Mg/ha) recorded for the 14 May planting date and the highest (3.50) for the 5 June date. The 76-cm row spacing outyielded the 38-cm by 0. 15 Mg/ha, and the earlier maturity variety outyielded the later by 0.30 Mg/ha. The earlier maturity group produced greater numbers of seeds and pods/plant and heavier 100-seed weight than the later maturity group. The 76-cm row spacing outperformed 38-cm rows in these same response variables. ROW SPACING AND PLANT POPULATION IN DRYLAND SUNFLOWER: Variables included 2 row spacings (38 and 76 cm), 3 plant populations (32300-low, 43000-optimum, and 64400-high plants/ha) and 2 sunflower types (oilseed and nonoilseed). The narrower row spacing produced a numerically greater seed yield each season for each variety type with the 4-year average difference being 224 kg/ha for oilseed and 600 kg/ha for nonoilseed. The "optimum" population produced as good or better yields than the other two during 3 of 4 seasons for each variety type. Only in one exceptionally good season did the "high" population result in higher yields. There was a strong tendency for narrower row spacing to produce greater amounts of crop residue (numerically greater 6 of the 8 variety years), but only one season of one variety was the difference statistically significant (5 percent). Stem diameter was little affected by row spacing, but consistently decreased with increasing population. The decrease was offset by increasing population, such that silhouette factor increased with increasing population. Weight per head also decreased with increasing population so no difference in lodging was observed. Seed yield over a 4-year period averaged 224 kg/ha greater in 38-cm rows than in 76-cm while the difference was 600 kg/ha for nonoilseed. Amounts of crop residue also increased, so less wind erosion hazard was associated with narrower rows.

IMPACT: 1996/10 TO 2000/09
In a wheat-summer crop-fallow rotation, results suggest available acreage be planted to both corn and sunflower with areas being sized according to weather and crop price outlook, need for crop residue, and availability of funding for production expenses. Yield and crop residue amounts of dryland sunflower were greater with 15-inch row spacing than with 30-inch while lodging was unaffected.

PUBLICATIONS: 1996/10 TO 2000/09
No publications reported this period

Item No. 18 of 34

INVESTIGATOR: Kelley, K. W.

PERFORMING INSTITUTION:
KSU SE AGRICULTURE RES CENTER
KANSAS STATE UNIV
MANHATTAN, KANSAS 66506

EVALUATION OF CROP ROTATION AND TILLAGE SYSTEMS FOR SOUTHEAST KANSAS

OBJECTIVES: 1) Evaluate effects of previous crop and N fertilizer (rate, time, and placement) on grain yield, yield components, and plant N uptake in no-till winter wheat. 2) Evaluate grain yield response, nutrient uptake, and weed control in different combinations of tillage systems using conventional tillage and no-till in a corn / grain sorghum - soybean - (wheat - doublecrop soybean) rotation. 3) Evaluate effects of soybean maturity and crop rotation on grain yield and soybean cyst nematode population in full-season and doublecrop soybean cropping systems. 4) Evaluate effect of various soybean and grain sorghum cropping sequences on grain yield, and yield componets. 5) Evaluate effect of soil pH on grain yield and nutrient uptake for wheat, soybean, and grain sorghum.

APPROACH: Replicated field studies will be conducted at the Southeast Agricultural Research Center. to evaluate effects of various cropping and tillage systems on grain yield, yield components, plant nutrient uptake, soil fertility, weed control, and plant and soybean cyst nematode infection.

PROGRESS: 1996/10 TO 2001/09
In a 20-yr long-term crop rotation study, soybeans grown in a 2-yr rotation averaged 16 percent higher yield than in a monoculture system. Yields were highest when soybean followed a wheat - summer fallow rotation or following grain sorghum, intermediate following wheat - double-crop soybean, and lowest for continuous soybean. Even though the site was soybean cyst nematode (SCN) infected during the last five years of the study, grain yields of both SCN resistant and susceptible cultivars were poorly correlated with SCN population. It is unclear why soybean yield differences between SCN resistant and susceptible cultivars of similar maturity were small in this study. Crop rotation did not consistently reduce final SCN population among susceptible soybean cultivars when grown one year after a non-SCN host crop. However, crop rotation significantly increased soil organic matter and total soil carbon (C) and nitrogen (N) in the 0-15 cm soil depth compared with monoculture soybean. Differences in soil properties among crop rotations were directly proportional to the total amount of crop residues produced during the 20 year period. From 1989 through 1998, six cropping systems including wheat and soybean were evaluated for effects on grain yield and economic returns. Treatments included: 1) continuous wheat - double-crop soybean maturity group (MG IV); 2) four 2-yr rotations of [wheat - double-crop soybean] followed by full-season soybean (MG's I, III, IV, and V); and 3) 3-yr rotation of wheat - wheat - full-season soybean (MG V). Wheat yields were highest following early-maturing soybeans (MG's I and III) and wheat following wheat. Wheat yields were lowest following late-maturing soybean (MG V) and in the continuous wheat - double-crop soybean system because of delayed planting date. Full-season and double-cropped soybean yields were influenced by cropping system, maturity group, and environment. However, soybean yields averaged over the 10-yr period were similar for MG's III, IV, and V, whereas MG I soybean yields were more variable. In the double-cropping systems, MG IV soybean often produced highest yields. Economic evaluations showed that in most years net income after variable costs were highest when wheat and double-crop soybean were grown in one or two year cropping systems and lowest for the 3-yr crop rotation with no double-cropping. In a 10-yr crop rotation and fertilizer N study where wheat was grown every 2 years, hard red winter wheat yields were influenced significantly by previous crop, tillage method, N rate, and N placement. Yields were significantly higher when wheat followed soybean compared to wheat following grain sorghum. Reduced tillage (disking) resulted in slightly higher grain yield than no-till, regardless of previous crop. Grain yields were significantly higher when liquid N was preplant applied below crop residues with a coulter-knife applicator compared with broadcasting liquid N on the soil surface. Where wheat followed grain sorghum, soil and fertilizer N likely were immobilized to a greater extent because of higher residue levels compared to soybean.

IMPACT: 1996/10 TO 2001/09
Results of long-term research studies show that soil quality and productivity are often improved over time when high residue-producing crops are grown in the crop rotation. In addition, with increased emphasis on soil and water conservation, keeping crop residues near the soil surface through the use of reduced tillage or no-till management practices in wheat and double-crop soybean rotations is beneficial to the environment.

PUBLICATIONS: 1996/10 TO 2001/09
1. Kelley, K.W. 2001. Planting date and foliar fungicide effects on yield components and grain traits of winter wheat. Agron. J. 93:380-389.
2. Kelley, K.W. 2001. Ten-year evaluation of wheat and soybean cropping systems. Agronomy Abstracts, c03-kelley092547-P.
3. Kelley, K.W. 2001. In 2001 Report of Agricultural Research, Southeast Ag Research Center, Report of Progress, No. 875, pp-50-59.

Item No. 19 of 34

INVESTIGATOR: Claassen, M. M.

PERFORMING INSTITUTION:
AGRONOMY
KANSAS STATE UNIV
MANHATTAN, KANSAS 66506

REDUCED TILLAGE & CROP ROTATION SYSTEMS WITH WINTER WHEAT, GRAIN SORGHUM, CORN & SOYBEANS

OBJECTIVES: A. Determine wheat response to reduced tillage systems and to 2-year rotations with grain sorghum, corn, and soybeans, respectively. B. Determine grain sorghum response to reduced tillage systems at early and conventional planting dates. Treatment effects will be assessed in terms of the following: 1) crop residue cover, 2) soil moisture utilization, 3) water infiltration rate, 4) soil organic C/N, 5) microbial biomass, 6) nutrient uptake, 7) incidence and severity of wheat diseases, 8) weed control, 9) grain yield and quality, 10) economic returns.

APPROACH: A field experiment will be conducted to achieve the objectives of the project. Scientists from several departments within Kansas State University will cooperate in this investigation.

PROGRESS: 1996/10 TO 2001/09
During a 5-year period, the effects of 19 tillage and rotation treatments on the production of winter wheat, grain sorghum, corn, and soybean were investigated. No-till winter wheat in annual rotation with row crops was compared with continuous wheat (WW) in burn (B), chisel (C), and no-till (NT) systems. Row crops after wheat were grown with NT or V-blade (V) tillage and compared with continuous sorghum planted at early (May) or conventional (June) dates in NT or C systems. WHEAT: Crop residue cover in wheat after corn, sorghum, and soybean averaged 70, 70, and 49%, respectively. WW-B, WW-C, and WW-NT averaged 4, 32, and 83% residue cover after planting. Highest 5-yr average yields of 3864 and 3689 kg/ha occurred in wheat rotations with soybean and corn, respectively. Significantly lower yields of 2964 and 2654 kg/ha/yr were produced by wheat in monoculture and in rotation with sorghum. WW-B, WW-C, and WW-NT averaged 3152, 2883 and 2863 kg/ha/yr. Tillage effect on wheat yield was not significant. Plant N concentration in wheat at late boot-early heading stage was highest in continuous wheat and wheat following soybean. Wheat after corn and sorghum were 11 and 19% lower in N than continuous wheat. Tillage did not affect wheat N level. ROW CROPS: Corn, sorghum, and soybean following wheat had an average of 32 and 79% crop residue cover after planting in V and NT systems, with only minor differences between rotations. Crop residue cover for sorghum after wheat was comparable to that of continuous sorghum at the same planting date. However, in continuous sorghum, residue cover was reduced 18% by delayed planting (June vs May). Tillage did not significantly affect row crop yields in any of the cropping systems. Wheat rotation benefitted sorghum by increasing flag leaf N 13% as well as improving grain yield. Sorghum after wheat produced 1248 kg/ha/yr more than continuous sorghum planted in May. Planting date effect on yield of continuous sorghum was significant at p=0.16, with sorghum planted near mid-May yielding 715 kg/ha/yr more than sorghum planted approximately one month later.

IMPACT: 1996/10 TO 2001/09
Because of low wheat prices and freedom under the current government farm program to grow crops in more diversified systems, producers have considerable interest in the merits of various crop rotations and reduced tillage practices. This long-term experiment has been providing important information on disease incidence, yield response, and economics of wheat rotations with corn, sorghum, and soybean in comparison with continuous wheat or continuous sorghum in reduced tillage/no-tillage systems.

PUBLICATIONS: 1996/10 TO 2001/09
1. Aller, T.D., J.R. Williams, R.G. Nelson, M.M. Claassen and C.W. Rice. An Economic Analysis of Carbon Sequestration for Wheat and Grain Sorghum Production in Kansas. Proc. Soil and Water Conservation Soc. 2001.
2. Bockus, W.W. and M.M. Claassen. Effect of cropping sequence and tillage on severity of leaf diseases on winter wheat, 2000. Biol. and Cult. Tests. 2001:S27.
3. Claassen, M.M., et. al. Harvey County Experiment Field research. Field Research 2001. Kans. Agric. Exp. Stn. Rep. Prog. 876:28-33.

Item No. 20 of 34

INVESTIGATOR: Kalita, P.; Barnes, P. L.

PERFORMING INSTITUTION:
AGRI ENGINEERING
KANSAS STATE UNIV
MANHATTAN, KANSAS 66506

MONITORIMG AND MODELING NITROGEN TRANSPORT AND LEACHING IN AND BELOW CROP ROOT ZONE

OBJECTIVES: Evaluate nitrogen (N) rates and sources surface broadcast in conservation tillage (high residue) cropping system. 2) Evaluate the use of urease inhibitor as an additive to urea containing fertilizers. 3) Evaluate the effects of previous crop residue (soybean and corn) on efficiency of surface broadcast N in conservation tillage systems. 4) Evaluate the chlorophyll meter as an in-field N assessment tool. 5) Monitor the effects of conservation tillage on soil nitrogen dynamics in and below the crop root zone. 6) Evaluate computer simulation models used to predict soil nitrogen dynamics in and below the crop root zone.

APPROACH: Objectives 1 through 4 will be accomplished by conducting field experiments at three experimental sites: Sandy Land, Scandia, and Rossville. Nitrogen rates, source, and effects of previous crop residue will be evaluated with 4 replications at each site. Objective 5 will be accomplished by monitoring soil nitrogen dynamics in and below the crop root zone. Soil and groundwater samples will be collected from each site and will be analyzed for nitrate-N concentrations in the soil profile and potential leaching to groundwater. Plant and grain samples will be collected for total nitrogen analysis. Data collectedfrom this study will be used for the modeling purposes as defined by objective 6. Two computer simulation models (LEACHM and NLEAP) will be used to predict nitrogen dynamics under conservation tillage systems. These two models will be corroborated to improve nitrogen transport predictions under conservation tillage systems in Kansas. First year#s field experiments were conducted the summer and fall of 1995. The second year#s experiments will be conducted during 1996-1997 period. Both years data will be used for computer model result verification.

PROGRESS: 1996/10 TO 1999/09
Monitoring and modeling studies for nitrogen transport and leaching were conducted throughout the year. For monitoring nitrogen leaching and transport, field experiments were conducted at Rossville, and lysimeter experiments were conducted in Manhattan, Kansas. The Rossville plots received 75, 150, and 225 lb-N/acre fertilizer application rate. Soil samples were collected twice a month from each plot during the growing season. Soil samples were collected from 6, 12, 24, 36, 48, and 60 inch depths. Water samples from 1, 3, and 5 ft. depths were collected through the suction tubes twice a month, but adequate quantity of water sample could not be collected most of the sample times. Lysimeters consisted of sandy and silty clay loam soils and received 200 lbs-N/acre fertilizer application rate. From the lysimeters, soil-water samples were collected for Nitrate-N concentration analysis. For modeling nitrogen transport and leaching, Leaching Estimation and Chemistry - Nitrogen (LEACHN) model has been used. Nitrate-N and NH4-N concentrations in soil and water have been simulated at several depths below ground surface. Input values for soil (hydraulic conductivity, bulk density, texture, etc.), climate (rainfall, temperature, humidity, etc.), and management (irrigation, crop, chemical application rate, etc.) parameters have been calibrated for appropriate input parameters. A very close correlation between model predictions and observed data on NO3-N was observed for most of the depths.

IMPACT: 1996/10 TO 1999/09
Models can be used, if they have been properly tested and verified, as an economic tool to predict the use and possible transport of contaminants in the environment. The models currently being tested have adequately predicted contaminant fate in the Kansas environment and can accurately assess sensitive sites in Kansas.

PUBLICATIONS: 1996/10 TO 1999/09
1. Borah, M.J. 1999. Monitoring and Modeling Water and Agricultural Chemical Transport in Intact Lysimeters. Ph.D. Dissertation, Kansas State University (P. Kalita Advisor)
2. Borah, M.J. and P.K. Kalita. 1999. Development and evaluation of a macropore flow component for LEACHN. Transactions of the ASAE, Vol. 42(1): 65-78.

Item No. 21 of 34

INVESTIGATOR: Kluitenberg, G. J.; Ham, J. M.; Barnes, P. L.

PERFORMING INSTITUTION:
AGRONOMY
KANSAS STATE UNIV
MANHATTAN, KANSAS 66506

SOIL MOISTURE MONITORING IN THE BLACK VERMILLION WATERSHED

OBJECTIVES: (1) Characterize spatial and temporal patterns of soil surface water content within a watershed of the Black Vermillion River. (2) Evaluate a heat-pulse technique for measuring soil surface water content. (3) Investigate the relationship between soil surface water content and atrazine loss due to surface water runoff events.

APPROACH: A heat-pulse technique will be used to characterize the spatial and temporal patterns of near-surface soil water content in a sub-watershed of the Black Vermillion. Laboratory experiments with desorption cells and containers packed with soil of known water content will be used to evaluate the accuracy and precision of the heat-pulse technique. Precipitation and near-surface soil moisture data for the sub-watershed will be coupled with surface water runoff volumes and water quality data obtained from another project to assess how antecedant soil moisture affects the quality and quantity of surface water runoff.

PROGRESS: 1997/01 TO 2000/09
The primary focus of this project was to evaluate dual-probe heat-pulse (DPHP) sensors for obtaining measurements of soil water content. Both laboratory and field experiments were conducted to perform this evaluation. The laboratory experiment was conducted using eight different soil materials with a broad range of physical properties and volumetric water contents ranging from 2 to 57 percent. The results for all soil materials were described by a single linear regression model, which indicates that soil-specific sensor calibration is unnecessary. A regression standard error of 2.2 percent showed that excellent precision was attained. Although the DPHP sensors showed slight bias towards overestimation of water content at lower water contents, the linear regression model can be used to correct for this bias. The field experiment was conducted in a sub-watershed of the Black Vermillion River (northeast Kansas) at locations with a variety of soil, crop, and tillage conditions. At each monitoring station, in situ water content measurements were obtained at 3-h intervals with 5 DPHP sensors buried horizontally, 10 cm below the soil surface. Water content was monitored continuously for 80-100 days at each station. Independent measurements of water content were obtained at all stations by periodically collecting soil samples. Volumetric water content data from all monitoring stations were pooled to examine the relationship between water content measured with DPHP sensors and the independent measures of water content. A linear relationship with a standard error of 2.7 percent was obtained. The conclusion of this work is that the DPHP method can be used successfully in both laboratory and field settings with excellent accuracy and precision.

IMPACT: 1997/01 TO 2000/09
This project evaluated a new method for measuring soil water content near the soil surface. This information is needed to provide improved understanding and prediction (modeling) of surface water runoff, a major mechanism for the loss of chemicals from agricultural fields. Better understanding and prediction of runoff will ultimately result in improved management of agricultural chemicals.

PUBLICATIONS: 1997/01 TO 2000/09
No publications reported this period

Item No. 22 of 34

INVESTIGATOR: Martin, V. L.; Warmann, G. W.

PERFORMING INSTITUTION:
AGRONOMY
KANSAS STATE UNIV
MANHATTAN, KANSAS 66506

ROTATION/TILLAGE ALTERNATIVES TO CONTINUOUS DRYLAND WHEAT ONSANDY SOIL

OBJECTIVES: Primary objective is to determine the agronomic and economic feasibility of three-year rotations vs. continuous wheat under the dryland sandy soil conditions and climate of south central Kansas. The second major objective is to determine what effect rotations will have in successfully eliminating tillage compared to no-tillage continuous wheat.

APPROACH: Eight different rotations (continuous wheat, continuous grain sorghum, and six other rotations involving wheat and corn or grain sorghum with or without fallow) will be replicated and split into conventional and no-tillage plots. With all possible rotations, this results in 20 rotation combinations; 40 treatments when tillage is included. The study will last through two rotation cycles, six years, and allow for determination of total productivity, observation of agronomic factors, and economic analysis.

PROGRESS: 1997/10 TO 2002/09
Despite reworking rotations to include broadleaf crops (sunflower, cotton, soybean) and the inclusion of glyphosate tolerant crops (cotton and soybean) in 1999, crop response to a total dryland no-tillage system was poor. Two primary factors were responsible. First, even with Roundup Ready technology, weed control, particularly crabgrass and Palmer Amaranth, was variable at best and typically quite poor. Two possible solutions to improve weed control are thermal weed seed management (burning) and a chemical fallow period. Burning is discouraged and a fallow season is undesirable from an economic standpoint. A practical solution is the introduction of a tillage rotation with tillage prior to wheat and broadleaf crops, and cultivations during broadleaf production. Second, the extremely coarse nature of the soils combined with low organic matter content, made planting and stand establishment difficult. Lack of soil structure combined with typical dry fall conditions made wheat planting and stand establishment difficult, even with >90% residue cover. The drought over the last several years also made the establishment of spring row crops difficult. Planting had to be delayed until adequate soil moisture was present to allow planting. As stated previously, a tillage rotation as outlined would help, particularly with wheat and broadleaf crops following all crops except wheat and no-tillage for corn and grain sorghum. Crop yields in this study were, on average, less than one-third those of adjacent studies using conventional tillage and a tillage rotation system.

IMPACT: 1997/10 TO 2002/09
Rotations where wheat is limited to one year in three resulted in better weed control and significantly great wheat yields during the wheat year of the rotation. Corn and sorghum are the most viable dryland rotational crops. Soybeans are very susceptible to late summer drought stress which significantly depresses yields. No-tillage is not improving yields for wheat, although no-till grain yields are not competitive with chisel-disk system for corn and grain sorghum.

PUBLICATIONS: 1997/10 TO 2002/09
No publications reported this period

Item No. 23 of 34

INVESTIGATOR: Lamm, F. R.

PERFORMING INSTITUTION:
KSU NW AGRICULTURE RES CENTER
KANSAS STATE UNIV
MANHATTAN, KANSAS 66506

MACROMANAGEMENT: IRRIGATION SCHEDULING TECHNIQUES FOR CORN

OBJECTIVES: Evaluate and develop criteria for terminating irrigation for corn. 2) Determine the optimum irrigation capacity for corn using sprinkler, surface or subsurface drip irrigation (SDI). 3) Develop precise irrigation/nutrient management strategies for corn using (SDI).

APPROACH: A study will examine the effect on corn production of terminating the irrigationseason on 5-day intervals beginning at tasseling over a 45 day period. Grain filling rates will be correlated to soil water and ET rates. Another study will examine the effect of irrigation system capacity on corn production for 3 system types (sprinkler, surface and SDI). The production functions and water use data will be used in simulated irrigation schedules for a 30 year period. Corn yields will be modeled according to calculated actual water use as related to the potential maximum water use. The economic analysis will compare the potential profitability as well as the historic weather-related risk to corn production levels. Another field study will examine methods of optimizing corn production with high frequency SDI and in-season fertigation.

PROGRESS: 1997/10 TO 2002/09
An irrigation scheduling model was combined with a yield production function and economic model to simulate crop yields and economics under four irrigation system/application efficiency combinations for 6 different irrigation capacities. Using 27 years of climatic data for western Kansas, center pivot sprinkler irrigation systems were found to give higher crop yields and greater profitability than furrow surface irrigation, particularly when system flowrates were less than 40 L/s. Sprinkler irrigation systems with application efficiencies of 100, 95, and 85% and a furrow surface irrigation system with 70% application efficiency produced simulated crop yields of 12.3, 12.2, 12.1, and 11.3 Mg/ha, respectively, when irrigation capacity was 6.35 mm/day. A study was conducted from 1997 to 2001 to determine the optimum corn plant population at various subsurface drip irrigation (SDI) capacities (0, 2.5, 3.3, 4.3, 5.1, and 6.4 mm/day). Results indicate higher plant populations (81,500-86,500 plants/ha) are optimum across a fairly wide range of irrigation capacities. Since seed corn costs can be $1.00 to $1.50/1000 seeds, this resource allocation is of great importance to producers. Results suggest an irrigation capacity of 4.3 mm/day is adequate SDI capacity when planning new systems in this region. Yields averaged approximately 15.7-16.3 Mg/ha over the course of 5 years when irrigation capacity was 4.3 mm/day or greater. An irrigation capacity of 4.3 mm/day is approximately 32% less than the full irrigation capacity for the region. It is concluded that small, daily amounts of water can be beneficial on these deep silt loam soils in limiting daily corn water stress, thus maintaining high corn yields. A field study to examine the effect of widely spaced (3.05 m) low-pressure spray nozzles at various heights in a corn canopy (0.6, 1.2, or 2.1 m) for irrigation capacities of 6.4, 5.1, 4.2, and 3.2 mm/day was completed in 2001. Analysis of multiple years' corn yields indicates that widely spaced nozzles are only appropriate near the tassel height (2.1 m). Corn yields were reduced by the wide nozzle spacing by approximately 0.8 Mg/ha from the nearest corn row to the furthest away from the sprinkler nozzle at the 0.6- and 1.2-m sprinkler heights. Irrigation capacities of 6.4 and 5.1 mm/day performed adequately over both relatively wet and extremely dry years, resulting in average yields of approximately 14.4 Mg/ha. The lowest two irrigation capacities had greatly reduced yields in the drier years (2000 and 2001) approximately 3.3 Mg/ha less than the adequately irrigated treatments. Average corn yields for the 0.6, 1.2, or 2.1 m sprinkler heights were 13.6, 13.1, and 13.5 Mg/ha. The 1.2-m height is the corn ear height, and the ear and large leaf area at this height make sprinkler irrigation distribution across rows more difficult.

IMPACT: 1997/10 TO 2002/09
Correct input allocation procedures allows producers to remain water efficient and economically viable. Incorrect sprinkler spacings and heights result in low water use efficiency that further depletes limited water supplies. Producers can easily recoup additional investment costs for correct 1.5-m sprinkler spacings when compared to yield reductions for the wider 3.05-m spacing.

PUBLICATIONS: 1997/10 TO 2002/09
No publications reported this period

Item No. 24 of 34

INVESTIGATOR: Barnes, P. L.

PERFORMING INSTITUTION:
AGRI ENGINEERING
KANSAS STATE UNIV
MANHATTAN, KANSAS 66506

EVALUATING GRASS FILTERS EFFICIENCY IN REMOVING CONTAMINANTS FROM SURFACE RUNOFF

OBJECTIVES: 1. To monitor field conditions that create runoff losses from field plots with slopes of 6 and 3 percent. 2. To monitor the mass balance of water, sediments, nutrients, and pesticides across a grass filter below field plots with various pesticide treatments on field slopes of 6 and 3 percent.

APPROACH: Runoff water will be collected for volume measurement and sub-sampled for contaminant concentration before itis redistributed and uniformly passed through a grass filter strip. After passing through the grass filter the runoff water will be collected for volume measurement and sub-sampled for contaminant concentration. These sata will be used to calculate a mass balance for the contaminants in the filter and the filters efficiency in reducing contaminant concentration and mass in the runoff water.

PROGRESS: 1997/10 TO 2001/09
To completely examine the efficiency of the grass filter strip in improving water quality, this sampling scheme examined both the filter inflow and outflow. The inflow portion consists of two components: 1) runoff from the field plot up-slope from the filter, and 2) rainfall that fell directly on the filter. If the two components of the inflow are added and then the outflow volume subtracted from the inflow, this value is a reasonable estimation of the infiltration. Nearly all of the literature on vegetative filters describes infiltration of runoff water as the primary mechanism for reduction of pesticides. Limited results have been presented to support this hypothesis. This study shows that application dates, other than at planting time, have significantly reduced loss of atrazine in runoff. If atrazine is dissolved in the water phase of runoff, then results suggest that the period with the highest potential for runoff losses of atrazine would be when it is applied at planting time. These runoff losses are the result of several factors such as antecedent soil moisture, rain depth and rain intensity. This study suggests that using a grass filter strip along with alternative atrazine application dates in the fall or early spring result in the most benefit from a grass filter. The grass filter system has the greatest atrazine loss if it is applied at planting time in May. These results suggest that additional practices beyond grass filter strips may be needed to clean up runoff.

IMPACT: 1997/10 TO 2001/09
During 2001, the State of Kansas has completed implementation on about 50% of the State's required Total Maximum Daily Loads (TMDL's) for sediments, nutrients, fecal materials, and pesticides. At the current time it appears that grass filters will be a cost and environmentally effective means to meet the requirements for these new TMDL's.

PUBLICATIONS: 1997/10 TO 2001/09
No publications reported this period

Item No. 25 of 34

INVESTIGATOR: Gordon, W. B.

PERFORMING INSTITUTION:
AGRONOMY
KANSAS STATE UNIV
MANHATTAN, KANSAS 66506

STARTER FERTILIZER APPLICATION EFFECTS ON REDUCED AND NO-TILLAGE GRAIN SORGHUM PRODUCTION

OBJECTIVES: The objectives of this research project are (1) to evaluate several methods of starter fertilizer application and (2) to determine the optimum rate of starter fertilizer in two reduced tillage crop production systems.

APPROACH: Field studies will be conducted at the North Central Kansas Experiment Field on a Crete silt loam soil. Tillage methods will consist of planting grain sorghum into crop residue with no prior tillage and planting with only one tillage operation designed to leave 50% of the crop residue on the soil surface. Methods of starter fertilizer application will include placement surface band and placement 2 inches to the side and 2 inches below the seed at planting. Liquid starter fertilizer treatments consist of various nitrogen-phosphorus combinations.

NON-TECHNICAL SUMMARY: The large amount of reside left on the soil surface in reduced tillage cropping systems can cause nutrient availability problems and slow crop growth which can ultimately reduce yields. This research is aimed at minimizing fertility problems that arise with reduce tillage systems thus making conservation tillage more attractive to producers. Methods of starter fertilizer application and rates of fertilizer will be evaluated.

PROGRESS: 2002/01 TO 2002/12
Conservation tillage production systems are being used by an increasing number of producers in the central Great Plains because of several inherent advantages. These include reduction of soil erosion losses, increased soil water use-efficiency, and improved soil quality. However, the large amount of surface residue present in reduced-tillage systems can reduce seed zone temperatures which may inhibit root growth and reduce nutrient uptake. Treatments in this experiment consisted of tillage systems (no-tillage and minimum tillage) and methods of starter fertilizer application (knifed-in 5 cm to the side and 5 cm below the seed at planting (5x5) and dribbled in a band on the soil surface 5 cm to the side of the seed at planting). Different combinations of liquid N-P2O5 fertilizer were also included. In both tillage systems, yields were maximized by application of starter fertilizer containing more than 17 kg N ha-1 in combination with 34 kg P2O5 ha -1. Low N starters or starters containing N or P alone were not as effective as starters containing higher amounts of N along with P. Use of high nitrogen starter fertilizer consistently increased grain yield, improved early season plant growth , decreased the number of days from emergence to mid-bloom, and reduced grain moisture content at harvest. Dribble application of starter fertilizer was as effective as subsurface 5x5 placement.

IMPACT: 2002/01 TO 2002/12
Success with conservation tillage depends in large part on fertilizer management. Starter fertilizer applied below the soil surface in reduced tillage systems can improve growth and yield of crops. Starter fertilizer containing at least 34 kg N and 34 kg P2O5 ha-1 applied either subsurface or dribbled on the soil surface significantly increased early season growth and yield of grain sorghum grown in reduced tillage systems thus minimizing fertility problems that arise with reduced-tillage systems. The results of this research make conservation tillage a more attractive option to producers.

PUBLICATIONS: 2002/01 TO 2002/12
1. Kansas Fertilizer Research, 2001. Report of Progress 885 p. 37-39. Kansas State University
2. Gordon, W.B. and D.A. Whitney, 2002.p. 132-137. In 2002 Fluid Forum Proceedings, 17-19 Feb. 2002. Fluid Fertilizer Foundation.,Scottsdale, AZ.
3. Gordon, W.B. and D.A. Whitney, 2002. P. 116-120. In North Central Extension-Industry Soil Fertility Conference Proceedings, 20-21 Nov. 2002.

PROJECT CONTACT:

Name: GORDON, W. B.
Phone: 785-335-2836
Fax: 785-335-2239
Email: bgordon@oznet.ksu.edu

Item No. 26 of 34

INVESTIGATOR: Janke, R. R.

PERFORMING INSTITUTION:
HORTICULTURE & FORESTRY
KANSAS STATE UNIV
MANHATTAN, KANSAS 66506

SOIL QUALITY TEST KIT DISTRIBUTION AND TESTING BY FARMERS

OBJECTIVES: 1. Assemble a suite of tests that will serve as a quantitative evaluation of important soil quality factors on Kansas soils. 2. Validate these tests by comparison with standard tests, and determine the number of samples required per field for an accurate assessment of each factor. 3. Obtain feedback from farmers on which tests provide meaningful results to them, which tests are useful, but too time consuming, and which tests need to be performed within a standardized lab setting. 4. Assemble and distribute soil quality test kits to farmers for "beta-testing" on their farms. 5. Determine the interest level among farmers in Kansas in purchasing a soil quality test kit, and find the means for distributing these kits.

APPROACH: Introduction: Research and dissemination of information on soil quality has increased greatly in the past few years. Much progress has been made, and several published documents define soil quality, describe physical, chemical, and biological properties associated with soil quality, and the cropping systems that help improve soil quality. Soil quality can be defined as "the fitness of a specific soil to function within its surroundings, support plant and animal productivity, maintain or enhance water and air quality, and support human health and habitation." Tests that are associated with soil quality include increasing levels of soil carbon or organic matter, the presence of water stabile aggregates, the absence of compaction (surface and subsurface), and appropriate levels of various crop nutrients and pH in the soil. Some success has been achieved in distributing soil testing tools to farmers, including the late spring nitrate test used to estimate nitrogen needs for corn in Iowa, Vermont, and in other states. Dissemination of soil quality test information is happening through the NRCS Soil Quality Institute, and in individual states. For example, the University of Maryland has published a Soil Quality Assessment Book and the University of Minnesota in collaboration with the Land Stewardship Project has published a unit on soil quality in their Whole Farm Assessment notebook. Dr. John Doran, USDA/ARS has put together a soil quality test kit for evaluation by researchers in collaboration with farmers. In Kansas, we have been field testing the kit proposed by John Doran, developing new tests, and trying out some additional tests proposed by other researchers. In workshops with farmers, we are finding that there is a great interest in being able to perform some tests on their own soils, to monitor progress when using soil improving practices. Particularly among organic farmers, where soil improving crop rotations are required for certification, farmers are asking how they can prove or validate whether their practices are in fact improving the soil. In a recent workshop in western Kansas, many farmers stated that printed information is helpful, but what they really needed was a package of tests, ready to use, that require a minimum amount of time, but are still quantitative enough to document real changes.

NON-TECHNICAL SUMMARY: Farmers will be asked to perform a series of tests on paired fields, to validate the test kit. Interviews, written surveys, and focus groups will be conducted with farmers who volunteer to participate. Distribution of a final version of the soil quality test kit will complete and accomplish the goals of this project. A control soil will also be supplied with the test kit, for comparison and calibration of the nutrient status tests and the aggregate stability test.