Growth Characteristics and Green Manure Productivities of Hairy Vetch and Woolly Pod Vetch under Different Sowing Seasons in the Highland Area

The highland area remained bare for the winter and spring seasons and this condition has resulted in soil erosion. In this areas, crop rotation by legume has not been commonly practiced. Thus, this study was carried out to evaluate the effects of the growth characteristics and nitrogen yield as a green manure crop according to sowing seasons of hairy vetch and woolly pod vetch. In this experiment, we was investigated the growth characteristics, winter tolerance, soil coverage and productivities of hairy vetch and woolly pod vetch. We cultivated two hairy vetch(Madison, H1) and two woolly pod vetch(Naomi, Haymaker) varieties in the highland are a from 2006 to 2007. The result are summarized as follows; The plant height of hairy vetch increased with the progress of growth stage until flowering stage. The wintering rate of hairy vetch was 79~83% in highland area. But, the wintering rate of woolly pod vetch was 29.5~39.2%. The 100% soil coverage of hairy vetch was reached between end of May and beginning of June under autumn sowing and between end of June and beginning of July under spring sowing The weeds density of hairy vetch field under autumn sowing was lower than that under spring sowing Dry matter yield of hairy vetch was significantly higher than that of woolly pod vetch under autumn sowing. The dry matter yield of hairy vetch and woolly pod vetch were 5,255~5,405 kg/ha and 3,520~3,640 kg/ha, respectively. But, hairy vetch in spring sowing was not significantly higher fresh matter yield than that of woolly pod vetch. The nitrogen content in hairy vetch and woolly pod vetch was 2.98~3.08 and 2.74~3.21%, respectively. There were no significant difference in nitrogen content of the hairy vetch and woolly pod vetch under the spring sowing. N-uptake of hairy vetch was significantly higher than that of woolly pod vetch in autumn sowing. The N uptake was 156~164 kg/ha in hairy vetch and 96~101 kg/ha in woolly pod vetch under autumn sowing. It was thought that hairy vetch was better than woolly pod vetch as a green manure crop in autumn sowing considering wintering rate and yield of dry matter in highland area. And woolly pod vetch could use as a green manure crop under spring sowing in highland area.