Weed management concerns are a major factor limiting producer adoption of conservation tillage cotton production in South Texas. In conservation tillage systems, pre-plant weeds are chemically controlled with a burn down herbicide, thus leaving the crop residue on the soil surface. Crop residue on the soil surface can interfer with traditional methods of incorporating soil applied herbicides prior to planting. Conservation tillage has several production advantages over conventional tillage systems such as reduced wind and water erosion, reduced time, labor, fuel, equipment, trips over the the field and increased net returns. The primary objective of this study was to determine weed management strategies for no-tillage cotton planted into corn and grain sorghum crop residue compared to conventional tillage cotton production. Weed populations, and plant growth and yield parameters were measured throughout the growing season. Weeds were controlled adequately by cultivation and herbicides currently available such as combinations of pendimethalin plus coteran or clomazone plus coteran. No-tillage cotton planted into corn or grain sorghum stubble show promise in this subtropical, semi-arid environment of the Lower Rio Grande Valley of Texas.