Weed Control by Means of Chemicals

Weed control by means of chemicals has become an important factor in our struggle to eradicate weeds. There are few weed problems which chemicals cannot at least aid. However, in many cases, their use is limited by their cost. It has generally been held that chemicals are too expensive for large infestations of weeds. In northwest Iowa where there are thousands of acres of European bindweed (Convolvulus arvensis L.) chemicals of the present day cannot be recommended on account of the cost. To control this noxious weed it has been necessary to resort to cultivation and competitive cropping, processes which take several years, and have for their objective a reduction in the amount of food reserves in the subterranean parts, to the point where there is not sufficient food material to regenerate new shoots