The major limiting factor in small ruminant production is gastrointestinal nematode (GIN) infection. Severe infections can result in low weight gain, milk production, and even death. Currently, there are no viable anthelmintic treatments for organic producers as available medication voids organic status. Recent research has shown that some tanniniferous legumes can suppress GIN infection while also providing great dietary benefits. One such legume is birdsfoot trefoil (BFT). BFT is well-adapted to the Northeast, can increase weight gain, milk production, and pasture quality. Although once established BFT can reseed itself, it has proven difficult to establish in pasture.
In order to reap the benefits of BFT, inhibitory interactions and seeding methods must be assessed. Very little work has been done to evaluate levels of allelopathic inhibition by forage grasses into which BFT is commonly seeded upon BFT establishment and persistence. I used leeched allelopathic compounds from plant material, living root exudates, and decayed root exudates from seven common, cool-season forage grasses to establish previously unknown levels of allelopathic inhibition. Preliminary results show significant allelopathic inhibition of BFT by endophyte infected tall fescue, reed canarygrass, smooth bromegrass, and perennial ryegrass. Conversely, meadow fescue and timothy did not significantly inhibit BFT germination.
The role of grass type (bunch or rhizomatous) in no-till BFT seeding is also unknown. I am using a split plot design and three seeding treatments (coulter, tine, and swath rototill) in pure stands and mixed stands to test the effect of grass type (rhizomatous or bunchgrass) on BFT establishment. Preliminary results are pending and will be available August 2020.
Results/Conclusions
Based on preliminary results, it is clear that a pasture’s composition is crucial in the success of BFT establishment in pasture. Due to the novelty of my research, more work must be done in order to have results producers may practically apply. Though allelopathy and pasture makeup are only parts of a greater framework, it is crucial to understand these interactions so that effective practices may be used and growers may reap the benefits of BFT.