识别杂草幼苗具有实际意义。首先,在防除上,大多数除草剂在杂草的萌发及幼苗期施用;其次研究杂草的生物学特性,为综合防除提供依据,也必须首先了解杂草的发生情况和幼苗形态;第三,杂草的花期较迟、较短,而苗期和营养生长期较长,在进行杂草调查时也必须熟悉各种杂草幼苗。但是,传统的植物分类主要是以花器为依据的,而有些同一科植物的幼苗往往有很大的差异,也有些不同科的幼苗又往往很为近似,如同属豆科的杂草天兰苜蓿和大巢菜幼苗的差异就很大,大巢菜子叶不出土,天兰苜蓿子叶出土。不同科的杂草如十 Identification of weed seedlings has practical significance. First of all, in the prevention and control, the majority of herbicides in the weed germination and seedling stage application; followed by the biological characteristics of weeds to provide a basis for comprehensive prevention and control, we must first understand the occurrence of weeds and seedling morphology; third , Weeds flowering later, shorter, and longer seedling and vegetative growth period, weed surveys must also be familiar with a variety of weed seedlings. However, the traditional classification of plants is mainly based on florida, while the seedlings of some common plants often have very different, but also some of the seedlings of different families are often very similar, such as the legume weed Tianlan alfalfa And the big difference between the large nestleaf seedlings, large neotropical rapeseed leaves unearthed, Ceylon alfalfa leaves unearthed. Weeds of different branches such as ten