A number of weed researchers, extension agronomists and weed specialists in Texas and Oklahoma were contacted to determine their perception of the areas where additional research is most critical in weed science. The following is a list of research areas that were mentioned most frequently

1. Limited Tillage Research a. Herbicide Systems b. Role of Alleopathy C. Herbicide Carryover Potential 2. Ecology and Biology of Perennial Weeds 3. Economic Thresholds 4. Weed Control Strategies For Perennial Weeds a. Silverleaf nightshade (Solanum elaegnifolium cav.) b. Nutsedges (Cyperus spp.) c. Horsenettle (Solanura spp.) d. Hog potato (Hoffmanseggia ensiflora Benth.) 5. Weed Control Strategies For Annual Weeds a. Morningglories (Ipomoea spp.) b. Devilsclaw (Proboscidea lousianica Mill. Thell.) c. Ground cherries (Physalis spp.) d. Croton (Croton spp.) e. Prairie sunflower (Helianthus petiolaris Nutt.) f. Cocklebur (Xanthium spp.) 6. Overtop Broadleaf Herbicides 7. Glandless Cotton Herbicide Response 8. Safeners For Chlorotriazine and Chloroacetamide Herbicides 9. Varietal Resistance to Herbicides 10.Herbicide - Soil - Ground Water Interactions 12. Application Technology 13.Breeding For Application Adaptation

In certain areas there is a place for some form of reduced tillage systems in cotton. The predominant use of preplant incorporated herbicides in Texas and Oklahoma precludes the maintenance of large amounts of crop residues on the soil surface. Economical grass control systems are needed in reduced tillage production regimes. Concern exists about the possible allelopathic effects of crop residues and alterations in persistence of various herbicides applied to heavy crop residue.

Perennial weeds and certain broadleaved annual weeds are not adequately controlled with present herbicides. Certain species in the Euphorbiaceae and Solanaceae families are especially troublesome and more efficacious herbicides are needed. Most preferable would be a selective overtop broadleaf herbicide that could be tank mixed with grass control overtop products currently registered for use in cotton.

An alternate avenue for pursuing improved broadleaf control is breeding cotton varieties that have tolerance to chlorotriazine herbicides that will control these weeds preemergence. Development of safeners that will allow the use of these herbicides in cotton is another possibility. Breeding a cotton plant that is more suited to directed postemergence herbicide applications early in the season was also suggested. Application equipment improvements is also a research need.

Additional research is needed in the area of herbicide-soil interactions as it relates to efficacy, persistence and leaching.

Herbicide-insecticide interactions are of increasing interest since the introduction of the selective overtop grass control herbicides. This very practical question needs to be addressed so that producers may be in a position to reduce trips across the field when product compatibility will permit.