"With the dry summer and fall we had last year, a lot of would-be alfalfa plantings were put aside," said Kansas State University agronomist Jim Shroyer. "Now we have the potential, from late March into early May, to get that crop in the ground."

Choosing disease-resistant varieties with a proven track record for your area and appropriate fall dormancy ratings is important, he said.

Tonnage from spring-planted alfalfa during the first year will not be as great as it would have been had the crop been planted last fall, said Shroyer, who is a crops production specialist with K-State Research and Extension. However, by 2002, production will be the same as if the field had been planted in the fall of 2000.

"If you’re shopping for new alfalfa seed to plant this spring, you should have no trouble finding some excellent new disease-resistant varieties," said Extension plant pathologist Bob Bowden. "Almost all new varieties now have good resistance to bacterial wilt, Verticillium wilt, Fusarium wilt, anthracnose race 1, and Phytophthora root rot diseases. Look for ratings of H (high resistance) or R (resistance) for each of these diseases. Ratings of M (moderate resistance) or L (low) are not adequate to prevent disease losses."

Good resistance to aphanomyces root rot race 1 is harder to find because the disease is relatively new, he added.

"Aphanomyces is favored by waterlogged soils, so resistance is a good idea on heavier soils, especially in eastern Kansas," Bowden said. "Resistance to alfalfa stem nematode is good insurance in south central, southeastern and southwestern Kansas where outbreaks occasionally occur."

Some companies have other special disease codes appended to the name of the variety, he said. Codes "EV" or "+Z" indicate the variety should have early vigor because it has been screened for resistance, using zoospores of Aphanomyces and Phytophthora.

"Of course, this should also be reflected in the resistance ratings for these two diseases," Bowden added.

Some companies summarize disease resistance into an overall Disease Rating Index. The index is the sum of the disease ratings for six important diseases. A high resistance rating gets a score of 5. A perfect rating index for resistance to all six diseases is 30 points.

"This works well since we now have so many good resistant varieties. It’s important to keep in mind, however, that several disease ratings – including stem nematode – are not included in the index," Bowden said.

Apron XL LS or Allegiance LS systemic seed treatments are often applied to alfalfa seed to protect against Phythophthora and Pythium seedling blight.

Such treatments are good insurance, especially in fields with a history of stand establishment problems, and would be especially appropriate with spring-planted alfalfa, given the often-wet conditions, Shroyer said.

"Don’t forget to also check for insect resistance ratings, yield performance, and fall dormancy ratings," he added.

Kansas alfalfa growers should look for fall dormancy ratings in the 3 to 5 range, Shroyer said. Ratings of 3 to 4 are best for the northern part of the state, and 4 to 5 are best for southern areas. The lower the number, the earlier the variety goes into dormancy and the less productive it is in the early fall, he explained.

More detailed information about alfalfa variety test performance can be found in the booklet 2000 Kansas Performance Tests With Alfalfa Varieties, available at county Extension offices.