Perennial Legumes for Sustainable Pasture Systems

Perennial Legumes for Sustainable Pasture Systems

Summary

The objectives for this project include:

1) To develop alternative strategies for establishment of kura clover and birdsfoot trefoil, and

2) To develop a new kura clover variety through plant breeding.

Field trials took place in Minnesota, Michigan and Wisconsin.

At the Repprecht farm in Lewiston, Minnesota, a pasture containing perennial grasses and small amounts of white clover was renovated. We compared no-till seeding with broadcast seeding in spring 1999 following tillage in spring 1999 and fall 1998. Fall tillage for grass suppression followed by spring seeding resulted in the best kura clover stands. No-till planting resulted in the poorest kura clover stands. Red clover that established likely volunteered from the seed bank or from seed contamination. We have noted that some lots of commercial kura clover seed have been contaminated with red clover. Grazing following seeding and during the summer was used to suppress competition from regrowing perennial grasses; however, it was not completely effective and all treatments had significant perennial grass populations.

At the Michaelis farm in Rollingstone, Minnesota, we studied establishment by broadcast seeding in spring 1999 following corn or perennial grass pastures. Corn was chisel plowed in fall 1998 while the pasture was either moldboard plowed or harrowed in spring 1999. Kura clover stands were greatest following fall tilled corn and moldboard tilled pasture. Both practices suppressed existing vegetation and provided a better seedbed than harrowing in spring.

At the Thicke farm in LaCrescent, Minnesota, existing vegetation in a perennial grass-legume pasture was suppressed using animal impact during the winter of 1998-1999. Three levels of impact were applied by varying the duration of animal exposure. Kura clover seed was broadcast and packed in the spring. Kura clover was seeded alone and in mixture with red clover. Heavy animal impact resulted in the best kura clover stands with low animal impact the poorest stands. Establishment of kura clover with red clover usually decreased kura clover establishment. By the fall, significant perennial grass populations had re-established for all treatments.

At the Minar farm in New Prague, Minnesota, existing vegetation in a pasture was suppressed and the seedbed prepared by harrowing either once or twice. The two-time disking treatment was designed to increase suppression of the existing grasses. At seeding, about 15 percent of the ground in the one-time disking treatment was covered by vegetation. Kura clover was broadcast seeded with a grain drill in mixture with birdsfoot trefoil and reed canarygrass. We also seeded a red clover-white clover-reed canarygrass mixture and a birdsfoot trefoil-reed canarygrass mixture. Similar kura clover stands were obtained with either one- or two-time disking while white clover and birdsfoot trefoil stands were better for the one-time disking.

At the Wiley farm in Kalamazoo, Michigan, we established pure stands of birdsfoot trefoil, kura clover and a mixture of birdsfoot trefoil and kura clover by broadcasting in an over-grazed pasture where sheep ewes had grazed. Because of wind drift on the planting day, pure kura clover plots were mixed with some trefoil. Therefore, results for botanical composition include both clovers and trefoil, even in plots sown only to clover. Birdsfoot trefoil plots contained only trefoil and no other legumes. However, kura clover plots were comprised of 33 percent trefoil and 67 percent kura clover. The seeded mixture of trefoil and kura clover contained 65 percent trefoil and 35 percent kura clover. Clover establishment was challenging at Kalamazoo because of severe summer drought.

At Staub Triple H Farms in St. Johns, Michigan, we conventionally planted strips of birdsfoot trefoil, kura clover and reed canarygrass. A dairy heifer herd will graze these strips in the second and subsequent years. The experiment showed that planted grass produced higher dry matter yields compared with volunteer grasses in birdsfoot trefoil and kura clover treatments. Also, planted legumes in the reed canarygrass mixture resulted in a higher legume biomass than volunteer legumes. Birdsfoot trefoil and kura clover had similar dry matter yields.

At the Bontekoes farm in Osceola County, Wisconsin, pastures were split into conventional and no-till establishment treatments. Each tillage system was planted to trefoil, kura clover and a trefoil-clover mixture using a drill planter. A significant tillage by treatment interaction was observed for composition and yield. No tillage establishment resulted in higher composition of legumes and grasses than conventional tillage. With conventional tillage, bare soil comprised 32 to 53 percent of the areas compared with only 3 to 17 percent in no-till treatments. Legume composition ranges were 11 to 36 percent and 54 to 87 percent in conventional and no-till establishments, respectively.

Successful kura clover establishment occurred at only two of the three Wisconsin on-farm sites. Plots were observed but no data was collected. Data will be collected in 2000 to quantify treatment effects.

For objective 2, we conducted an additional cycle of selection for seedling vigor in the field.

Collaborators: