Method for selectively controlling plant suckers

摘要

Methods for controlling parasitic plant suckers growing from desired vegetation are disclosed which involve selectively contacting the foliage of the plant sucker with an aqueous solution containing a urea-sulfuric acid component which is a reaction product of urea and sulfuric acid, and avoiding contact of the remaining foliage of the desired vegetation with the aqueous solution. The molar ratio of urea to sulfuric acid in the urea-sulfuric acid component is preferably within the range of about 1/4 to about 7/4, and preferably at least about 25 percent of the sulfuric acid in the urea-sulfuric acid component is present as the monourea adduct of sulfuric acid. The aqueous solution may also contain an amount of a surfactant sufficient to increase the wetting ability of the solution for the foliage of the plant sucker to accentuate the herbicidal activity of the solution toward the plant sucker.