Great Water Dock
Rumex hydrolapathum
Great Water Dock is an impressive, perennial marsh plant primarily found along the banks of water bodies. Reaching heights of up to 2.5 meters, it is the largest native dock species in Europe. Its leaves are lanceolate and can reach an impressive length of up to one meter. The plant plays a vital ecological role as a host plant for specialized insect species and contributes significantly to bank stability.
Details
Oxygen production
Minor oxygen release through roots into the anoxic sediment (Radial Oxygen Loss).
Habitat function
Serves as a spawning substrate for insects and as a hiding place for juvenile fish in shallow water zones.
Nutrient uptake
High capacity for nitrogen and phosphate uptake, contributing to water purification.
Food source for
Large Copper butterfly, Green Dock Beetle, various weevil species.
Human use
Historically used as a medicinal plant (astringent) for skin conditions and scurvy; roots are rich in tannins.
Ecology
Ecological role
Primary food plant for the larvae of the endangered Large Copper butterfly (Lycaena dispar); provides cover for waterfowl.
Natural predators
Leaf beetles (e.g., Gastrophysa viridula), aphids, and various gastropod species.
Competitor species
Common reed (Phragmites australis) and other large-growing reed bed plants.
Ecosystem service
Bank stabilization through its massive root system; nutrient retention from water and sediment.
Threats
Destruction of natural riparian zones, drainage of wetlands, and overly intensive watercourse maintenance (mowing).
Scientific profile
Profile
Reproduction
Generative via buoyant fruits dispersed by wind (anemochory) and water (hydrochory). Vegetative via strong, perennial rhizomes.
Protection & threats
Main threats
Loss of wetlands due to drainage, intensive shoreline engineering, removal of reed beds, and severe water level fluctuations.