Integrated Management and Ecology of Weed Populations in the Southeastern Coastal Plain

Wiley C. Johnson, III and Theodore M. Webster

1. What major problem or issue is being resolved and how are we resolving it?
Cotton, peanut, and vegetable are important crops in the southeastern coastal plain. Sustainability of these systems is currently challenged by the increasing costs of crop production inputs while crop prices remain stagnant or decline. We are studying cost-effective systems of weed management with less dependence on herbicides. Integrated weed management systems are being developed and implemented using knowledge of weed control (e.g. modified cultural practices, alternative tillage methods, computer decision support systems) and weed biology (e.g. weed propagule ecology, weed seed germination patterns).

2. How serious is the problem? Why does it matter?

Production costs for weed control are a major input for producers in the southeastern coastal plain. Acreages of cotton, peanut, and vegetable crops within this area have always fluctuated due to environmental conditions and economic constraints. However, these commodities consistently account for a significant proportion of the total agricultural value in the region

Weed management in peanut and vegetable crops is difficult and costly, with herbicides (including methyl bromide fumigation for vegetables) being the primary component of most weed management systems. Therefore, farmers are spending more for herbicides, while weeds are still causing major losses. Clearly, the state of weed management has not improved in recent years, despite new herbicide developments. Effective integration of cultural weed controls, alternative tillage systems, and current weed control practices will result in improved weed management and lower unit production costs in agronomic and vegetable crops in the southeastern coastal plain.

1. How does it relate to the National Program(s) and national Program Components(s)?

The incumbents' programs are dedicated to long-range, high-risk research on anticipated or emerging agricultural problems. This project directly addresses high research priorities in ARS National Programs 304 (Crop Protection and Quarantine) and 308 (Methyl Bromide Alternatives) in the pest management discipline: current integrated weed management technology is inadequate to assure effective, safe, and economical weed control, agroecosystem productivity, and environmental quality. Currently, the incumbents have the only active weed science research project on vegetable crops in Georgia, and only one of three in the southeastern coastal plain. The remainder of the incumbents' assignment is on weed science research on peanut, cotton, other agronomic crops, and turfgrass. The incumbents' project is the only one in the U.S. actively investigating alternatives to herbicides for weed control in peanut; specifically alternative cultural weed control systems and modified tillage practices.