Meadow fescue seeding rate impacts mixtures with alfalfa on marginal sites

摘要

Abstract Alfalfa (Medicago sativa L.)–grass mixtures are often used to provide high‐quality dairy forage in the northeastern United States. Meadow fescue (Festuca pratensis Huds.) is popular as a companion for alfalfa in the region because of its high nutritive value. We aimed to evaluate alfalfa–meadow fescue mixtures in northern environments that are unsuited to alfalfa production. Our study was conducted in the year after seeding at two northern New York sites. A reduced‐lignin [fall dormancy (FD) = 4] and a conventional alfalfa (FD = 3) were seeded with diploid and tetraploid meadow fescue varieties in replicated plots, with five seeding rates for meadow fescue. Dry matter yield increased linearly with increased meadow fescue seeding rate. The meadow fescue percentage of mixtures had a curvilinear response to meadow fescue seeding rate, increasing from 44% at the 0.5 lb acre–1 seeding rate to 67.4% at the 4 lb acre–1 rate. Tetraploid meadow fescue had a smaller grass percentage in mixtures and higher nutritive value than a diploid meadow fescue. Reduced‐lignin alfalfa was not greatly different in nutritive value from a conventional cultivar under unfavorable environmental conditions for alfalfa production. We conclude that meadow fescue should be seeded at a very low rate (1 lb acre–1) with alfalfa in northern environments that are unsuitable for alfalfa. Moreover, reduced‐lignin alfalfa (FD = 4) may not result in large increases in nutritive value compared with conventional cultivars selected for high nutritive value on marginal northern sites better suited to FD 3 cultivars.