Submitted to: Agronomy Journal
Publication Type: Peer reviewed journal
Publication Acceptance Date: 5/7/2004
Publication Date: 9/1/2004
Citation: Teasdale, J.R., Devine, T.E., Mosjidis, J.A., Bellinder, R.R., Beste, E.C. Growth and Development of Hairy Vetch Cultivars in the Northeastern United States as Unfluenced by Planting and Harvestins Date. Agronomy J. 96:1266-1271. Interpretive Summary: Hairy vetch has become an important cover crop for use in sustainable agricultural cropping systems. It can serve many important functions including fixing and producing nitrogen for use by succeeding crops and improving soil quality. In no-tillage production, it provides a mulch on the soil surface that moderates soil temperature, conserves soil moisture, and suppresses weeds and pests. New cultivars of hairy vetch were developed at Auburn University that had not been tested in the northeastern U.S. We conducted trials at Beltsville, MD, Salisbury, MD, and Freeville, NY to evaluate the performance of these cultivars at different planting and termination dates. Results showed that the Auburn cultivars were less winter hardy in New York and they did not produce more vegetative biomass or nitrogen than the common hairy vetch currently available commercially. However, they flowered 15 days earlier than common hairy vetch and could be a useful alternative to Maryland producers who need an earlier flowering cultivar. In addition, this research provides guidelines for determining the optimum time of planting hairy vetch in order to achieve ground cover before winter and high biomass production in spring. This research will be useful to scientists, extension personnel, and growers that use cover crops.
Technical Abstract: Hairy vetch (Vicia villosa Roth) is a winter annual legume that has become an important cover crop for sustainable production systems. New cultivars of hairy vetch, developed in the southern U.S., need to be tested as cover crops in the northeastern states. Research was conducted at three locations (Salisbury, Maryland; Beltsville, Maryland; and Freeville, New York) that represent a gradient from a relatively mild coastal climate to a colder interior climate. Four cultivars of hairy vetch (the unnamed "common" hairy vetch that is sold commercially and three cultivars developed at Auburn University, AU Early Cover, Advanced Population 8, and Advanced Population 26) were planted at either optimum or delayed dates and were harvested at either vegetative or full flowering stage. Common hairy vetch biomass was equal to or better than the Auburn cultivars at all locations and years. The Auburn cultivars were winter hardy under Maryland conditions but not under New York conditions. The Auburn cultivars reached 50% flowering an average of 15 days earlier and reached 50% senescence an average of 7 days earlier than common hairy vetch. Delaying planting by two to three weeks reduced biomass by 43% when harvested vegetative and by 20% when harvested at flowering, whereas, delaying harvest from vegetative to flowering stage increased biomass by 37% for the early planting and by 95% for the late planting. Hairy vetch growth and development could be predicted on the basis of growing degree days (GDD) with a base temperature of 4EC. The number of GDD to achieve 50% soil cover by hairy vetch vegetation in late fall was predicted by an exponential model to be 655 while the GDD to achieve a biomass of 400 g m-2 in spring was predicted by a linear model to be 926. When planted at an optimum date, 1112 and 1350 GDD were required for AU Early Cover and common hairy vetch, respectively, to reach 50% flowering. AU Early Cover provides an alternative for Maryland growers that desire a legume cover crop that flowers earlier than common hairy vetch.