Restructuring littoral zones: a different approach to an old problem

Published source details Engel S. (1984) Restructuring littoral zones: a different approach to an old problem. Lake and Reservoir Management, 1, 463-466.
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Summary

Action: Use cutting/mowing to control problematic plants

A before-and-after study in 1977–1982 in a lake in Wisconsin, USA (Engel 1984) reported that cutting aquatic vegetation changed the relative abundance of macrophyte species. Statistical significance was not assessed. In the three summers before harvesting, the aquatic vegetation was dominated by Berchtold’s pondweed Potamogeton berchtoldii and sago pondweed Potamogeton pectinatus (72–92% of total biomass). In the two summers during/after harvesting, the aforementioned pondweeds were still abundant (28–65% of total biomass) but there now also a substantial proportion of curly-leaf pondweed Potamogeton crispus (17–60% June-July) and coontail Ceratophyllum demersum (20–33% August). In the summer after the final harvest, the most abundant species were Berchtold’s and sago pondweed (17–53%) along with water stargrass Heteranthera dubia (10–67%). Methods: Aquatic macrophytes were cut and removed from Halverson Lake in June and July 1980 and 1981. Around 50–70% of the existing vegetation was removed each year between 0.5 and 1.5 m depth. Remaining macrophytes were sampled by divers in June, July and August 1977–1982, then cleaned, dried and weighed.