A long-lasting herbicide product may sound good, but there are dangers in applying some of these products to eliminate weeds. The key ingredient that provides extended weed control belongs to a group of compounds called the imidazolinones. Two of these compounds, imazapyr and imazapic, are water soluble, persistent in the soil, and can be taken up by the roots of weeds and desirable woody ornamentals alike. Be sure to read, and carefully follow, all labels and look particularly for words like ‘extended control’ or ‘kills weeds for up to one year’ on the container.
Misapplication of these extended control products can result in plant damage and death. Symptoms include strappy, small, and twisted tufts of foliage, dieback, and plant death. If you are working near trees and shrubs, check that the chosen herbicide can be applied to these root zones or damage could result.
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