Transplant mesocosm experiment for two macrophytes under different trophic conditions.
Hydrilla verticillata has significant growth potential in eutrophic conditions.
Failure of Hydrilla verticillata to colonize eutrophic system might be herbivore regulated.
Cabomba caroliniana growth impaired by low nutrients and high pH reservoir water.
Cabomba caroliniana may have minimal risk of spread in region based on water chemistry restrictions.