Hairy vetch biomass yield as affected by fall planting date in the irrigated steppe of the southern Rocky Mountains

Mid- and late-summer plantings of hairy vetch grow well in the steppe of the southern Rocky Mountains represented by the Espa (n) over tilde ola Valley (elev. 1740 m) of north-central New Mexico; however, little or no information exists on the relationship between fall planting date and biomass yield the following spring. We conducted an experiment under furrow irrigation in which hairy vetch was planted at approximate to 19 kg/ha on or about September 2, 16, October 1, 16, and November 3 in 1997, 1998, and 1999. Our objective was to determine the effect of fall planting date on aboveground dry matter weight (DMW) during mid-April and mid-May of the following spring. Averaged across all three years, April DMWs were 3210, 1720, 373, 106, and 21 kg/ha for the September 2, 16, October 1, 16, and November 3 plantings, respectively. May DMWs averaged across three years were 4650, 3130, 1300, 707, and 247 kg/ha for the September 2, 16, October 1, 16, and November 3 plantings, respectively. (C) 2003 by The Haworth Press, Inc. All rights reserved.