These data are collected to document and characterize the submersed macrophytes of Trout Lake, to evaluate the long-term stability of this component, and to interface with investigations of other compartments of the ecosystem. Four sites along the shoreline of Trout Lake have been sampled annually in August along permanent line transects. This dataset includes biomass per m2 for individual species summarized by depth along the transect. Derived data include the mean and standard deviation of macrophyte biomass. These data are useful in determining the annual variability of the submersed macrophytes and providing information on the effects of the invasion of an introduced crayfish. Sampling Frequency: annually during summer Number of sites: 4