Introduction to the symposium on site-specific weed management

Abstract

Since the dawn of civilization, humans have practiced site-specific weed management. In its earliest form, weeds were visually identified as such and removed by hand (should this be referenced as “sight” specific weed management?). Hoeing or hand weeding is even today one of the most important weed management tools worldwide. Even with the development of herbicides, a number of methods have been used for site-specific management. Producers and land managers mentally mark the location of a weed patch and later apply a pre- or postemergence herbicide at that location. The rope-wick applicator is based on the principle of applying a herbicide only where a weed is standing above the crop. I can remember as a teenager spending days on a tractor driving up and down peanut (Arachis hypogea L.) rows and turning a sprayer loaded with 2,4-DB off and on based on where horsenettle (Solanum carolinense L.) patches were located. It was common for a number of years in the Mississippi Delta to see a tractor with a bar on the front that had four to eight seats welded to it, with riders watching for johnsongrass [Sorghum halepense (L.) Pers.] in cotton (Gossypium hirsutum L.) fields and applying a nonselective herbicide such as glyphosate, or later selective ACCase-inhibiting herbicides.