THE BIOLOGY OF CANADIAN WEEDS.: 34. Myriophyllum spicatum L.

A review and information from recent research are provided on the biology of Eurasian watermilfoil, a weed species introduced from Eurasia, that occurs in lakes in British Columbia and in lakes and rivers of Eastern Canada, especially those close to the St. Lawrence Seaway. A table of characteristics that distinguish this species from M. exalbescens and M. verticillatum is provided. No single method of control offers the possibility of complete eradication; but the best ones include mechanical harvesting, the use of the selective herbicide 2,4-d, contact herbicides Diquat and Paraquat, rototilling and diver-operated dredges.