Welcome to the University of Georgia Weed Science Homepage.

The weed science faculty and staff are committed to providing the information and resources you need to answer your weed control questions.

Managing Herbicide-Resistant Palmer Amaranth (Pigweed) in Field Corn, Grain Sorghum, Peanut, and Soybean - 2017

The occurrence of herbicide resistance in Palmer amaranth and other weeds in Georgia is cause for significant concern for the agricultural industry. Changes in cropping practices, specifically the reliance on a limited number of herbicides, have streamlined weed management. However, the consequence has been the development of herbicide resistance. An effective herbicide-resistant weed management plan will require the integration of multiple herbicide chemistries in an effort to minimize selection pressure and delay the occurrence of herbicide resistance in a field. Other control strategies, such as tillage, extreme cover crops, narrow row spacing, hand-weeding, crop rotation, and mechanical cultivation must also be included in an herbicide resistant weed management plan.

Read about managing herbicide-resistant palmer amaranth . . .

Methyl Bromide Alternatives 2016

Effective alternatives to methyl bromide exist but selecting the ideal fumigant, mulch, and herbicide program is challenging. Growers must better understand how soil texture, moisture, bed compaction, and their cultural practices influence fumigant activity, planting intervals, and off-gassing concerns. This circular is provided to assist growers with developing the most effective fumigant system for their farm.

Read about methyl bromide alternatives . . .

UGA Weed Control Programs for Wheat in 2015/2016

Ryegrass threatens Georgia wheat production, with numerous populations resistant to Osprey, PowerFlex, Axial and Hoelon. Aggressive resistance management programs must be implemented to ensure long-term sustainability of grain production.

Wild radish is the most problematic broadleaf weed infesting Georgia wheat, but management is not difficult if timely management decisions are implemented.

This circular is an effort to provide effective weed management programs for Ryegrass and Wild Radish in Wheat.

Read about wheat weed control programs . . .

UGA Weed Control Programs for Broccoli, Cabbage, and Cauliflower in 2016

Crop rotation, tillage, and a sound herbicide program are all often critical components for long-term success. This ciruclar focuses on developing sound herbicide programs while minimizing crop injury for the following production systems: 1) transplanting into mulch, 2) transplanting into bareground, and 3) seeding into bareground.

Read about broccoli, cabbage, and cauliflower weed control programs . . .

UGA Weed Control Programs for Watermelon in 2016

New herbicidal tools are being developed to assist growers in the battle against weeds in watermelon. These tools are a result of cooperative efforts involving The University of Georgia, IR-4, The Georgia Department of Agriculture, The Georgia Agricultural Commission for Vegetables, and Industry. This circular is an effort to provide effective weed management programs for seeded and transplant watermelon.

Read about watermelon weed control programs . . .

UGA Programs for Controlling Palmer Amaranth in 2016 Cotton

It is imperative that growers continue to use sound herbicide programs but also integrate these programs with other control measures, such as hand-weeding, to remove escapes before seed are produced, deep turning to reduce the number of plants emerging (ideally wait 3.5 to 4 years before repeating), and/or using a heavy mulch cover crop to suppress emergence in conservation tillage systems.

These integrated programs proved to be very successful. Continued efforts are underway to further improve management programs while becoming more economical.

Rolling Rye For Conservation Tillage Cotton Success

View the video...

The Biology and Ecology of Palmer Amaranth: Implications for Control

Palmer amaranth is a highly competitive weed of field corn, cotton, peanut, and soybean and has been confirmed to be resistant to glyphosate in nearly every agronomic county in GA. Glyphosate-resistant (GR) Palmer amaranth’s establishment and spread has been assisted by its rapid growth rate, extensive rooting structure, high seed production, physical seed movement (man, animal, water), and most importantly by pollen (wind) dispersal.

Growers must understand the biology and ecology of GR Palmer amaranth if effective control is to be achieved.

University of Georgia Herbicide Programs for Tropical Spiderwort Control in 2013 Cotton

Tropical spiderwort is a noxious, exotic, invasive weed that can spread quickly. Upon initial observation, tropical spiderwort appears to be a grass. While not a grass, it is a monocot (in contrast to broadleaf weeds, which are dicots) with leaves and stems usually fleshy and succulent. The stems will creep along the ground and root at the nodes. Vegetative cuttings from stems are capable of rooting and reestablishing following cultivation. Tropical spiderwort will produce seed above and below ground.


We are continually adding new information to our website.

If there are additional topics or resources that are of interest to you, please describing what you are looking for.



This website may contain research results of use patterns of herbicides, some of which may not be currently registered for the particular use. Such results are included for informational purposes only and should not be taken as recommendations for use. Additionally, the University of Georgia does not guarantee nor warrant the standards of the products, nor do they imply approval of the products to the exclusion of others which may be similarly effective. Official University of Georgia weed control recommendations can be found in the latest edition of the Georgia Pest Control Handbook (Special Bulletin #28).