Kura Clover: A New Legume
for Sustainable Pasture Systems in Michigan

Richard H. Leep, Peter Jeranyama, and Timothy Dietz*

ABSTRACT           

Kura clover (Trifolium ambiguum Bieb.) is slow and difficult to establish, yet when established, has good persistence and forage quality. An on-farm experiment with producers was established in Clinton, Kalamazoo and Osceola counties in Michigan to evaluate alternative establishment strategies for Kura clover using a research and demonstration network. Kura clover was established under no-till or conventional tillage systems in either pure or mixed stands with birdsfoot trefoil (Lotus corniculatus L.) (BFT) or reed canarygrass (Phalaris arundinacea L.) in Clinton county. Visual assessments of ground cover and botanical compositions were taken at least one time during the growing period. In some instances actual components yields were clipped and assessed as dry matter yield. Ground cover in conventional tillage system was 60 and 70% for pure stands of Kura clover and Kura clover in Kura-BFT mixtures, respectively. In no-tillage, ground cover was at least 80% for both treatments. Kura clover component in botanical composition was highest in no tillage compared with conventional tillage, but the former was associated with increased weed pressure. Kura clover produced up to

900 lb acre^-1 in the seeding year. We have learned that Kura clover is more difficult to establish than alfalfa or birdsfoot trefoil. The best establishment methods have been conventional seeding; however, direct drilling was successful in several locations and especially in Northern Michigan. The seeding establishment success seems to depend more on good weed control or suppression of grasses during the first six weeks of growth of Kura clover.

Objective 1.  To evaluate alternative establishment strategies for Kura clover using a research/demonstration network.

The productivity of many pastures in Michigan could be greatly improved through the addition of a truly perennial legume.  Legumes are important for profitable grazing management because they fix atmospheric N, has greater energy intake potential than grasses, and they improve seasonal distribution of pasture yield.  The potential acreage in Michigan, which could benefit from a perennial legume that never, requires reseeding, is huge.  There are about 1 million acres of permanent pastures.  If a persistent legume were present live weight gain could be improved a minimum of 100% compared to unimproved pasture production.  In addition, elimination of the necessity to reseed legumes into the existing ½ million acres of improved pastures would result in annual savings of $750,000.00.  Greater use of pastures will reduce the dependence of our society on resource consuming tillage-based cropping systems. __________________________________________________________________

* Extension Specialist and Professor, Postdoctoral Research Associate, and Research Assistant. Dep. of Crop and Soil Sciences, Michigan State Univ. East Lansing, MI 48824

Unfortunately, currently used legumes like alfalfa, red clover, white clover, and birdsfoot trefoil require careful management to be productive and do not reliably persist under Michigan environmental conditions. We propose to use Kura clover as a new model technology to promote pasture renovation with legumes.  Kura clover is a relative new perennial legume that is productive and persistent in pastures.  It has survived 15 years of intensive grazing in Minnesota and has persisted when all other legumes have died.  It has a deep, branching taproot and produces rhizomes (horizontal below ground stems), which enable it to spread vigorously.  The aboveground portion of Kura clover is very leafy and high in feeding value.  In recently completed research, Minnesota researchers found Kura clover forage contained 90% leaves, 25% crude protein, and was 83% digestible.  The tremendous potential of Kura clover is limited by difficulty in establishment due to its poor seedling vigor.  Alternative establishment strategies have not been evaluated on farm to maximize Kura Clover establishment. 

Summary

We have learned that Kura clover is more difficult to establish than alfalfa or birdsfoot trefoil. The best establishment methods have been conventional seeding; however, direct drilling was successful in several locations and especially in Northern Michigan. The seeding establishment success seems to depend more on good weed control or suppression of grasses during the first six weeks of growth of Kura clover. In a separate on-station trial we found that both Kentucky bluegrass and Timothy are the most compatible cool-season grass species for establishment with Kura clover, and by the end of the second year of production, there was little Kura clover in the stand with those species.

Methods and Approaches

On-farm projects were established at Kalamazoo, Clinton (St. Johns) and Osceola counties, MI looking at Kura clover (Trifolium ambiguum Bieb.) establishment and management. The experimental combinations comprised tillage and species mixtures, unless otherwise stated differently. Kura clover was either established in no-till or in conventionally tilled fields. In the no-till weeds were killed by glyphosate. Kura clover variety Endura was either seeded alone or in mixture with birdsfoot trefoil variety Norcen. In all treatments, Kura clover or birdsfooot trefoil was inoculated with appropriate rhizobia. We made visual assessments on ground cover and botanical compositions at each on-farm site. At Kalamazoo, the Wileys established pure stands of birdsfoot trefoil (Lotus corniculatus L.), Kura clover and a mixture of birdsfoot trefoil(BFT) and Kura clover in an overgrazed pasture. Sheep ewes had previously grazed the land. At St. Johns, (Mr. Howard Stroub) planted strips of  BFT, Kura clover and reed canarygrass (Phalaris arundinacea L. ). A dairy heifer herd grazed these strips in the second year. In Osceola county, the Bontekoes split their pastures into conventional and no-tillage establishments. Each tillage system was planted to BFT, Kura clover and a mixture of BFT and Kura clover using a drill planter. Data collected at these projects included botanical compositions and dry matter yields.

RESULTS:

1999 Growing season

Because of wind drift on the planting day at Kalamazoo, pure kura clover plots ended up being mixed with some BFT. Therefore results for botanical compositions include both clovers and trefoil even in plots meant for clover. In Kalamazoo, BFT plots comprised of pure BFT and no other legumes were observed. However, kura clover plots resulted in 33% BFT and 67% kura composition (Table 1). The mixture of BFT and kura indicated that 65% of composition was BFT while kura comprised of 35% (Table 1). Kura establishment is a challenge especially in the seeding year. Therefore the observed trend at Kalamazoo is not coincident, particularly because this location experienced a severe drought in summer.

The experiment in St. Johns showed that planted grass (reed canarygrass) produced higher dry matter yields compared with volunteer grasses in BFT and Kura treatments (Table 2). On the other hand planted legumes (BFT and Kura) resulted in a higher legume biomass than volunteer legume(s) in the reed canarygrass. However BFT and kura were not significantly different from each other in dry matter yields at this site.

Botanical compositions at St. Johns favored grass in the reed canarygrass treatment and legume in the BFT treatment (Table 3). The closeness of botanical compositions within the kura clover treatment seems to suggest a state of co-existence among the species.

In Osceola county, a significant  tillage X treatment interaction was observed. No tillage establishment resulted in higher compositions of legumes and or grasses than conventional tillage. In conventional tillage, bare soil comprised of 32-53% of the areas (Table 4) sampled compared with only 3-17% in no tillage treatments (Table 5).  Legume compositions ranges were 11-36% and 54-87% in conventional and no tillage establishments, respectively.

2000 Growing Season

Plant counts at Lake City, MI.  Plant counts showed very little differences between conventional and no-tillage establishments (Table 6). However, in each case, no-till was associated with more plants than conventional tillage. More plants were recorded in the BFT/Kura mixture than in sole treatments of the components present. There were more Kura plants in the sole Kura than in the mixture of BFT/Kura in the no-till, but not so in the conventional tillage (Table 7).

Visual Assessments at the Bontekoe farm, Osceola Co., MI.

Conventional tillage was associated with more plants than no-till (Table 8). Also, there were fewer Kura plants that they were BFT plants in either conventional or no-till.

Composition in Conventional. It is worth noting that even in treatments of Kura alone, some BFT plants were present in large populations. However, Kura clover was never present in the BFT alone treatment (Table 9). Naturally seeded white clover was a major component with a range of 27- 43%. Weeds accounted for at least 17% of composition. Kura composition was highest in BFT/Kura mixture but, was less than 15% of the sward.

Composition in No-till. In the no-till the two major constituents of the swards were weeds, which accounted for up to 50% of composition and naturally seeded white clover. Planted legume (BFT or Kura clover) accounted for less than 20% of the swards (Table 10).

Visual Assessments at the Stroub farm, Clinton Co., MI.

There were no significant differences in ground cover among treatments. The average ground cover was 74% (Table 11). Kura clover and BFT comprised 48 and 75% in swards, respectively (Table 11). Volunteer legumes, especially white clover comprised 40% with Kura, 24% with reed canarygrass and 12% with BFT. Reed canary grass was the only planted grass and comprised 75% of sward. In other treatments volunteer grass was approximately 12%. Ground cover averaged 65% and there were no differences among treatments (Table 7). Planted legume was 24% BFT and 32% Kura clover.

Involvement of other Audiences

Pasture walks were held at Clinton, Kalamazoo,  Ingham, Missaukee and Osceola counties in 2000 featuring Kura clover establishment. A field day is being planned for Lake City Experiment Station in the summer of 2001 in which, Kura clover research findings will be highlighted. Results of on-farm Kura clover establishment have been published in the Michigan Hay and Grazing Council Newsletter, a quarterly newsletter, which is distributed to graziers in MI.  In addition, a Kura clover Symposium is being planned for the Great Lakes International Grazing Conference at Battle Creek, MI in the winter of 2002. This conference will feature research results and experiences by farmers in Michigan and other states on Kura clover.

Farmer Adoption, Impact and Involvement

Many farmers in Michigan have indicated a clear choice to begin using Kura clover as a sustainable legume in their pastures after observing the Kura clover demonstrations at pasture walks.  They have learned from these demonstrations that good weed control is absolutely necessary during the establishment phase of Kura clover.  The demonstrations will be helpful in reducing failures in establishment of the crop as farmers could clearly see the need for careful preparation needed to grow the crop. 

Table 6. Tillage effects on plant count in 0.25 m² quadrat at Lake City, MI in 2000.

 

Table 7. Tillage effects on Kura clover plant count in 0.25 m² quadrat at Lake City, MI in 2000.

Table 8. Visual compositions at the Bontekoe farm, Osceola Co., MI in 2000.

Table 9. Visual compositions in conventional tillage at Bontekoe farm, Osceola Co., MI in 2000.

Table 11. Visual assessments on 28 April, 2000 at the Stroub farm, Clinton Co., MI.

Table 12. Visual assessments on 10 November, 2000 at the Stroub farm, Clinton Co., MI.