The growth and distribution of the aquatic vascular plants in nine lakes in western Massachusetts were examined in the field for two growing season. The objective of the study was to relate the growth and distribution of the vegetation to trophic levels in acid and alkaline lakes. Environmental parameters monitored included pH, total alkalinity, Secchi transparency, temperature, dissolved oxygen and conductivity. Nutrient levels were found by analysis of surface lake waters and plant shoot tissues for nitrogen and phosphorus. No significant correlations were obtained in these analyses. The distribution of the aquatic vegetation was correlated with total alkalinity and conductivity. Three groups of species were noted, those of waters with an alkalinity greater than 40 ppm CaCO3, those of waters with an alkalinity less than 40 ppm CaCO3, and those occurring regardless of alkalinity. Substrate also exerted a strong influence on plant distribution. No plants were found growing below the thermocline in the lakes sampled. Vegetative growth of the aquatic plants generally followed a standard growth curve. The standing crop was correlated with growth form and depth. Standing crops ranged from 0.3 to 420 g/sq m dry wt. Some difficulty was encountered in correlating plant growth with other parameters of trophic level. (Author)