Producers could easily and economically control broadleaf weeds in grass crops that previously had required mechanical or hand removal. Use of these materials spread rapidly and has continued to grow with the discovery and registration of new herbicides.
Weeds vary in susceptibility to herbicides.
Some weeds tolerate herbicides and others do not. For example, morningglory and other broadleaf plants tolerate Fusilade DX, while annual and perennial grasses do not. Herbicide labels and weed response tables provide growers with this information, but there is also variation in control within a particular genus or species. Selected plants of a species normally controlled by a herbicide may require slightly higher application rates for an acceptable level of control. For example, in a particular field or year, Treflan may not control smooth pigweed as well as it does in other fields or years.