During four growing seasons, aquatic vascular plant production and distribution were studied in Pat Mayse Lake, Texas, a 2425 hectare oligo-mesotrophic reservoir. The dominant macrophyte population was Myriophyllum spicatum L. Growth rates and regrowth rates of mechanically harvested Myriophyllum beds were found to be dissimilar. Based on estimates of watermilfoil nutrient content, there were insufficient nutrients in the entire population to alter the trophic status of this reservoir should all of the nutrients be instantaneously released. Sediments were the primary nutrient (nitrogen and phosphorus) sink. Bank erosion and solids transport from the watershed appear to contribute most of the sediments and a lake-wide mean sedimentation rate of 2.5 cm/year was estimated from sediment trap and core sample data.