2017 ASHS Annual Conference

A strong demand for locally-grown food has supported an expansion of peri-urban vegetable production in the northeastern US. Growers in this market actively embrace season extension technology, and the production season in much of the region now extends from April through December. Farmland is scarce and expensive, leading growers to plant all their acreage to cash crops every year, and to multi-crop fields used for short duration vegetables. In the past farmers have relied on winter cover crops such as cereal rye (Secale cereale L.) to maintain soil organic matter, but rye seeded after mid-October and terminated in April produces little biomass. Buckwheat (Fagopyrum esculentum Moench) is the standard cover crop in the Northeast for short duration summer fallows. Although an excellent crop for suppressing weeds, buckwheat biomass degrades quickly and contributes little soil organic matter. The objective of this study was to evaluate the summer annual grasses teff (Eragrostis tef (Zucc.) Trotter) and Japanese millet (Echinochloa esculenta (A. Braun) H. Scholz) as alternatives to buckwheat for use as short duration cover crops in areas of the Northeast with mild maritime climates. Researchers evaluated seeding rates and planting dates for both species in the summers of 2015 and 2016 at the Gardiner Crops Research Center in Kingston, RI. Teff was seeded at rates of 7.7, 9.4, 13.2, and 19.8 kg/ha of coated seed; Japanese millet was seeded at rates of 12, 24, 36, and 48 kg/ha. All seeding rates of teff resulted in excellent performance. Teff biomass exceeded 2000 kg/ha at six weeks after seeding, and reached 6.5 t/ha by ten weeks after seeding. Japanese millet gave significantly better performance seeded at 36 or 48 kg/ha than when seeded at lower rates. A seeding rate of 48 kg/ha was most effective at suppressing weeds, and produced 8 t/ha of dry biomass at 8 weeks after seeding, significantly more than the other rates. The 36 kg/ha seeding rate reached 8 t/ha biomass 10 weeks after seeding. Both teff and Japanese millet were seeded biweekly from 20 May until 15 August. Researchers measured crop and weed biomass at 6 weeks after planting, and crop biomass at 8 weeks after planting. Teff gave acceptable weed suppression and biomass production when seeded between 15 June and 30 July. Japanese millet performed poorly when seeded in May or August; performance in June and July varied across years.