Abstract: In this paper, the author expounded that in order to control weeds, the biological characteristics of weeds growing under different conditions should beinvestigated understanding the relationship betwe en weeds and environmental conditionsis the main basis for weed control, especially for its ecological control, The carter must be considered as the main chain, combining with chemical control and other agricultural measures, Only so doing, can the weed control be high-effective, safe and economic.

Key words: Algae, Growth inhibition test, Soil, Toxicity