２００１年，莱州市麦田杂草扁穗雀麦（BromuscatharticusVahl．）大面积发生，全市发生面积１．５万hm２，占全市小麦播种面积的３７．５％，其中较重发生的面积４００hm２。据笔者调查，受害田内平均有该草７．５株／m２，重者达十几至几十株，以致在田内形成“草坪”。扁穗 In 2001, Laizhou wheat field weeds Bromus catharticus Vahl. Occurred in a large area, the city has an area of ​​15000 hm2, accounting for 37.5% of the city’s sown area of ​​wheat, of which the heaviest occurred area 400hm2. According to the author’s investigation, the average number of the affected fields in the affected area was 7.5 / m2, with a maximum of more than 10 to several 10, resulting in the formation of “lawn” in the field. Panicle