苜蓿播种当年安全越冬与其生长生物量、分枝数、根颈入土深度及根颈粗细密切有关，引起赤峰地区近几年苜蓿越冬困难的主要原因是生产中苜蓿播种较晚造成其生长量不足和根颈入土较浅。试验表明，适时带肥早播促进苜蓿幼苗快速生长和封冻前浅耕覆土增厚根颈的保温层，能有效地提高苜蓿的越冬率 The main reason for overwintering of alfalfa in Chifeng area during the year of planting sowing alfalfa in winter is related to its growth biomass, the number of branches, the depth of root entry into the soil and the root and neck thickness. Root neck into the soil shallow. Tests showed that timely sowing with early sowing fertilizer to promote the rapid growth of alfalfa seedlings and thickening of the thickening of the root collar before freezing soil insulation can effectively improve the overwintering rate of alfalfa