Leaf-specific post-emergent herbicide application

Glyphosate had been used for decades as a pre-emergence herbicide in commercial agriculture. The introduction of herbicide-resistant GMO soybeans and other herbicide-resistant crops made glyphosate the most popular herbicide for grain farmers in the U.S. As the use of glyphosate in post-emergence applications increased, several important weeds, among them Palmer amaranth or pigweed (Amaranthus palmeri), and mare's tail also called horseweed (Conyza canadensis), adapted varieties resistant to this non-selective systemic herbicide. In the last 10 years, a growing number of acres of otherwise arable land have been abandoned to weed species that cannot be effectively managed in an economically viable manner.This proposal offers a new approach to weed management for commercial agriculture; a means to apply herbicide exclusively to weeds in the presence crop plants. The proposed approach combines an autonomous carrier platform to navigate the field, a machine vision system to identify plants of interest and to direct the pointing and operation of a precision, leaf-specific herbicide applicators. These applicators, can be pointed at specific plants and parts of plants such as the leaves to project very small quantities of concentrated herbicide onto specific locations with great precision. The ability to apply any herbicide directly and exclusively to weeds in the presence of the crop expands the number and types of herbicides, including those herbicides previously restricted to burn-down applications, that can be now be applied in a post emergence herbicide treatment.While the primary purpose of the proposed system is weed control, it provides several other potential advantages to commercial farming. Among these are: (1) a means to geolocate and monitor the progress of specific plants during the growing season by capturing and saving images collected during repeated trips through the field; (2) scouting for pests and diseases as well as estimating yields and variations in yields across fields; (3) the ability to determine herbicide effectiveness on a plant-by-plant basis and to collect evidence of crop damage due to splatter or drift; (4) to more accurately verify herbicide resistance in weeds to better control the statistical models used in combined experiments and split-plot field trials as well as identifying and harvesting herbicide-resistant weed seed for agricultural research.