Cover Crop Potential In Forage Crop Biomass Productivity.

Forage crops have gained interest as a potential source of biomass. However, more focus should be on cropping systems, including annual cover crops to increase their productivity. This study was done to identify the agronomic and forage potential of eight different cover crops on four different annual forage crops, to produce biomass as a source of lignocellulosic feedstock to produce ethanol. The experiment was conducted at two locations in Fargo and Prosper, ND. The experimental design was a randomized complete block design with a split-plot arrangement where the cover crop was in the main plot and the forage crop in the sub-plot with three replicates. All eight cover crop species were planted 9 August 2010. Just before the expected hard frost (14 October, according to previous data), foliar samples were collected to evaluate forage yield and quality. Results across locations indicated that forage pea (Pisum sativum L. cv. Arvika) had the highest dry matter yield (3238.3 kg ha^-1) followed by forage turnip Pasja [hybrid forage brassica (forage turnip X forage rape)], forage radish (Raphanus sativus var. niger cv. Daikon) and purple top turnip (Brassica rapa var. rapa). There was no significant difference in yield among the above mentioned cover crops. Further, forage pea N uptake was 126 kg N ha^-1 and forage radish, forage turnip, and purple top turnips N uptake was 65 to 68 kg N ha^-1. This indicates that forages peas fixed about 60 kg of N ha^-1 in only 40 days in the fall. In the spring of 2011, four different forage crops will be grown and their biomass yield and forage quality parameters will be analyzed. From those crops forage sorghum (Sorghum bicolor L. Moench) is expected to have the highest biomass yield and forage barley (Hordeum vulgare L.) the highest forage quality.