莴苣是菊科一年或二年生蔬菜。主要栽培季节为春、秋两季。莴苣的根系较浅,是一种对除草剂较敏感(易产生药害)的作物,一般不使用化学除草剂。但对常年栽培莴苣,杂草又比较严重的,选择化学除草就非常有讲究,菜农可根据发生的主要杂草种类,适当的时期选用合适的除草剂。 Lettuce is one year or biennial vegetable of Asteraceae. The main cultivation season is spring and autumn. Lettuce shallow roots, is a herbicide more sensitive (easy to produce phytotoxicity) crops, generally do not use chemical herbicides. However, perennial cultivation of lettuce, weeds and more serious, the choice of chemical weeding is very particular about vegetable farmers can occur according to the main weed species, the appropriate period of use of appropriate herbicides.