Changes in submersed macrophytes in Chautauqua Lake, 1937–1975

SUMMARY. Changes in macrophyte richness, relative abundances, depth distributions and dominant species from 1937 to 1975 were assessed in Chautauqua, a eutrophic lake. Change was greatest in dominant species, with several formerly abundant native Potamogeton species being replaced by the exotics, Potamogeton crispus and Myriophyllum spicatum. Two extensively practiced management techniques, herbicidal poisoning and mechanized cutting, were considered to be primarily responsible for the observed macrophyte changes.