Pleurisy Root
Asclepias tuberosa
This
is a beautiful plant that is a standout on the prairie. It produces a bright
orange flower and then gorgeous fruit pods in the late summer. The common name,
pleurisy root, comes from the use of this herb by both the Native Americans and
Pioneers to treat lung inflammations, or pleurisy.
Family:
Milkweed
Life cycle:
Herbaceous perennial, zone 4-9.
Native:
Great Plains of North America;
frequently seen in the Flint Hills of Kansas, though the plant is now on the
United Plant Savers at-risk list. This plant should not be wild harvested.
Height:
24 inches
Sun:
Full sun
Soil:
Well drained soil. Tolerates dry, sandy, and
rocky soil.
Water:
Low to moderate.
Flowers:
Brightly colored orange flowers bloom in
midsummer.
Propagation:
Stratify seed for at least 1 month then sow
indoors. In 2-3 weeks seedlings will appear at around 40-50% germination.
Transplant out in mid-late spring. Sow directly in the field in late winter or
early spring. Plant 12 inches apart. Grows in mounding clumps.
Harvesting:
Harvest the root in the fall after the plant has
gone to seed. Roots may be dug with a garden fork or needle nose spade.
Parts used:
Roots, dried. Do not ingest any other part of
this plant.
Used as:
Tincture, elixir, syrup, found in some medicinal
tea blends.
Medicinal benefits:
Recommended for respiratory conditions, coughs,
as an analgesic and to ease breathing. Also used as a diaphoretic and
expectorant.
Market Potential:
Low to moderate. Price range $8.50 to $46.40
for retail, bulk dried (cut and sifted) herb (see Appendix B.).
KSU Field Trial Data - 2000-2002.
(Note: two bio-types were grown in the field -
one more adapted to silt or sand soils, and one selected by the seed company for
sites with more clay. Both types have been averaged in this table, but
performed slightly differently at our different sites. For detailed site
information, see Appendix C.)
|
BUTTERFLY MILKWEED |
|
|
|
|
|
|
|
1st Year |
2nd Year |
3rd Year |
Average |
Comments |
|
|
|
|
|
|
|
|
Location/Years |
6 |
4 |
4 |
|
|
|
Survival (%) |
66.9 |
47.3 |
52.0 |
55.4 |
We aren’t sure how
to explain the increase in % survival from year 2 to year 3, except that
some plants apparently re-grew from the roots after harvested as data
plants. |
|
Vigor (rating) |
3.1 |
3.4 |
3.5 |
3.3 |
|
|
Height (cm) |
28.4 |
49.5 |
60.5 |
46.1 |
|
|
DW Herb (g/plant) |
6.3 |
89.1 |
104.7 |
|
|
|
DW Root
(g/plant) |
4.3 |
42.7 |
61.9 |
|
|
|
Maturity (rating) |
2.5 |
5.0 |
4.0 |
3.8 |
Plants were in full
flower during harvest in years 2 and 3. |
|
Insect (rating) |
0.6 |
1.0 |
0.7 |
0.8 |
Aphids. |
|
Disease (rating) |
0.2 |
1.7 |
1.0 |
1.0 |
|
|
|
|
|
|
|
|
|
Est. planting
density |
43,560 |
43,560 |
43,560 |
|
Assume 12” x 12”
spacing. |
|
Plant density x
survival. |
29,142 |
20,604 |
22,651 |
|
|
|
kg/acre DW (g/plant
x # of plants - roots) |
125 |
800 |
1402 |
|
|
|
Est. Marketable
Yld
(DW lb/acre
roots) |
276 |
1938 |
3088 |
|
|
|
Yld x ˝ of “low”
price - roots |
$1173 |
$8237 |
$13,125 |
|
|
|
Yld x ˝ of “high”
price - roots |
$6403 |
$44,962 |
$71,642 |
|
|
|
|
|
|
|
|
|
Summary of
Field Trial Data:
This plant germinates fairly well in
the greenhouse, once the seed is stratified. However, plants seem to lack
vigor when young, and are easily attacked by various greenhouse pests.
Once in the field, the plants seem to need extra attention the first year to get
started, as they are quite small. By the second year, plants that have
survived become more vigorous. Insect and disease pressure were not
severe, but small, first-year plants seemed to host a large number of bright
yellow aphids, which weakened the plant, but usually did not kill it.
This may be a good long-term crop
for growers seeking some diversification, as the roots generally wouldn’t be
large enough to dig until the second or third year, or later. Prospects for
sales are moderate, but the root is found in some commercial cold remedy tea
formulas. Ironically, as a native plant to central Kansas and the Great Plains,
one would expect exceptional vigor, but this plant only rated a slightly above
average rating of “3.3” averaged over all years and sites.
