The Lower Rio Grande Valley (LRGV) in south Texas is one of the most productive agricultural regions in southern United States. With subtropical climate and highly fertile soils, this region provides a year-round growing condition for crops. Along with citrus, major crops grown in the region are sorghum cotton and corn in the summer and vegetables in winter. Thus, a fallow period of 3-6 months between successive crops is common in the re-gion. Growers in this region report weeds as their number one economic and agronomic problem affecting crop yield and quality and increasing the cost of production and weeds account for the largest annual loss agricultural produce. In addition to the agronomic weeds, South Texas also has invasive non-native plants which result in eco-nomic or environmental consequences. Traditionally, land managers and farmers have depended on chemical and cultural (mowing/cultivation) methods for weed management. These methods are costly, labor intensive and might potentially pose environmental problems. With additional challenges posed by herbicide resistance in weeds and changing weather patterns, weed management is an important consideration for the growers in this region. Under-standing the weed ecology and biology should be part of developing and maintaining an effective weed manage-ment strategy for the LRGV. Here we present a review on the most economically and agronomically important weeds and their management options in the LRGV region
