“早期抽苔”是当归生产的大敌,是造成当归减产的主要原因。怎样解决这一问题呢?“立秋直播”便是行之有效的途径之一。一、“立秋直播”为何不抽苔?1974—1976年我们在太白县药场(海拔1700米)用老熟兆子(即早期抽苔的种子)进行了当归的分期播种试验,试验的结果表明,随着播期的推迟,早期抽苔率降低。在“立秋”前后(八月初)播种者,到第二年全部未抽苔。(表一) “Early bolting” is the enemy of Angelica production, is the main reason for the reduction of angelica. How to solve this problem? “Live in autumn” is one of the effective ways. First, the “Vertical Autumn Seeding” why not bolting? 1974-1976 we Taibai County (1700 meters above sea level) with the old mature trillion (that is, the early bolting of seeds) carried out angelica staged sowing test results It showed that the early moss rate decreased with the delay of sowing date. Before and after “Liqiu” (early August) planters, by the second year all were not bolted. (Table I)