Analysis of variance for cover crop winter ground cover as influenced by cover crop and planting date treatments and year.

*, **, and *** indicate significance at P Analysis of variance for cover crop winter ground cover as influenced by cover crop and planting date treatments and year.

*, ** 及 *** 分别表示在P水平下具有统计学显著性。本研究针对覆盖作物（cover crop）冬季地表覆盖，开展方差分析以探究覆盖作物、播种日期处理及试验年份对其的影响。