Some large harvesters are not easily maneuverable in shallow water or around docks or other obstructions. Many small fish and insects are often collected and killed by the harvester. Harvesting creates plant fragments which may increase the spread of invasive plant species such as Eurasian watermilfoil throughout the waterbody. Although harvesters collect plants as they are cut, not all plant fragments or plants may be picked up. These may accumulate and decompose on shore.
Harvesters are expensive and require routine maintenance.
Otherwise new exotic species could be introduced to the waterbody. Permits Harvesting in Washington requires hydraulic approval from the Department of Fish and Wildlife . Some Shoreline Master Programs may also require permits for harvesting. Check with your city or county before proceeding with a harvesting project. Because harvesting collects fish along with aquatic plants, some additional monitoring may be required when harvesting in salmon bearing waters, or a permit may be denied.