What's eating my common club-rush?

Common Club-rush is notably pest-resistant in its natural wetland habitat. Moth and midge larvae can bore into tall stems, and muskrats cut stems at the waterline to use as food and nesting material. Waterfowl graze young shoots in spring. Established stands in deeper water are largely self-sufficient and recover quickly from browsing or insect damage.

Stems cut at or below waterline for food and lodge-building; visible stumps and sections of floated stem near burrow entrances Plant in water deeper than muskrat foraging depth (over 60 cm / 2 ft where possible); wire mesh protection around container plantings; large natural stands recover without intervention

Boring into hollow stems causes individual shoot collapse; affected stems turn brown and die back while surrounding stems remain healthy Remove and dispose of collapsed stems to reduce larval carry-over; Bt spray on young emergent growth; no practical pond-safe insecticide for established stands

Young emerging shoots grazed in spring; uprooting of shallow-planted rhizomes; can slow establishment of new plantings significantly Protect new plantings with wire netting until well established; plant in water at least 30 cm (1 ft) deep; mature clumps tolerate seasonal grazing