为充分利用高原有限的热量资源，提高栽培牧草产量和种草的经济效益，设置了一年生禾草不同播期的产草量比较试验。结果表明，一年生禾草在川西北高寒牧区种植，最适播种期应在月平均气温达到２℃以上，土壤解冻后１０ｄ左右，约４月中下旬，最迟不得超过５月下旬。 In order to make full use of the limited caloric resources of the plateau and increase the economic benefits of planting forage and planting grass, a comparative experiment on grass yield of annual grass in different sowing dates was set up. The results showed that the annual grasses were planted in the alpine pastoral area of ​​northwestern Sichuan. The optimum sowing date should be above 2 ℃ in monthly mean temperature, about 10 days after thawing in soil, about mid-late April and late in May.