herbicides
Chemicals applied to vineyards to control the growth of weeds. They may be either pre-emergent (or residual) or post-emergent (knockdowm). The latter group comprises two types, contact and syntemic herbicides. Residual herbicides act against germinating seedlings of the weeds, while post-emergent herbicides are applied only to the strip of ground directly under the vine, and weeds growing between the rows are controlled by cultivation or mowing.