Roundup herbicide is a systemic weed and grass killer. When sprayed upon any unwanted growth, including corn, the plant moves the chemical to the roots, causing the plant to die. The green growth on corn must be sprayed so most of it receives the chemical. One application is sufficient.
About this Author
Lisa Larsen has been a professional writer for 18 years. She has written radio advertisement copy, research papers, SEO articles, magazine articles for "BIKE," "USA Today" and "Dirt Rag," newspaper articles for "Florida Today," and short stories published in Glimmer Train and Lullwater Review, among others. She has a master's degree in education, and is a member of the National Society of Collegiate Scholars.