Reproduces quickly through seed dispersal and horizontal root systems Create thickets in standing water and wetlands. Fragments of the yellow flag can form new plants when they break off Density poses a threat to native wetland species as it excludes plant and animal diversity. The removal of yellow flag requires labour intensive removal of root systems. Yellow Flag Iris (Iris pseudacorus)

Giant Hogweed (Heracleum mantegazzianum) Highly competitive plant: vigorous early season growth, abundance in full shade, tolerance of seasonal flooding. Up to 100,000 winged seeds (per plant), remain for up to 15 years. Removal of mature plants=manual removal of the first 8-12 cm of the central root. Immature plants= cutting the plants at ground level and covering the soil with black plastic. After removal, mow the site every two weeks to exhaust the seed bank in the soil (for 3-5 years) Giant hogweed contains a clear, highly toxic sap that causes burns, blisters and scarring. Anyone in contact with plant must wear heavy, water resistant gloves and coveralls that completely cover the skin

Himalayan Blackberry (Rubus discolor) Spreads by root and stem fragments. Birds and omnivorous mammals consume berries and disperse seeds, which can lay dormant for years. This invasive specie favors disturbed sites such as streambeds, roadways and forest edges. The Himalayan Blackberry is a threat to riverbanks, because it outcompetes deep rooted native shrubs by limiting light exposure, resulting in increased erosion of the banks. The removal of Himalayan Blackberry requires labour intensive removal of its root systems.

English Ivy (Hedera helix)

Policemans Helmet Goutweed/Bishop’s Weed

1) Manual removal of the taproot. Taproot removal is most effective from early spring (April) to early summer (July). Be sure to do this more than once as year, as plant can re-sprout. 2) Removal of flowering heads. Cut all flowering heads with garden clippers or scissors just below the bloom. The collected flowers should be contained and disposed in a landfill. Giant hogweed flowers from late June to mid September. 3) Repeated mowing. Useful when a lot of giant hogweed plants are present on large, flat sites. Mowing should be repeated continuously, on three-week intervals, throughout the growing season (April-November). 4) Application of diluted glyphosate. Herbicide that should be used sparingly to control giant hogweed. It can be applied directly to the leaf surface with a paintbrush or inserted into the stem. Herbicide application is most effective in early spring (April). A second application later on in the growing season (approx. June) is often required. Effective control methods- Giant hogweed

1)Manual removal of the plant and rhizome: Requires pickaxes or crowbars. Easiest immediately after the pond water level has fallen, but the soil is still wet (late June-early July) Done annually. Reduce amount of disturbed soil. Replant with native or non‐invasive vegetation to stabilize against erosion. The collected plants should be contained and disposed in a landfill. 2)Removal of flowering heads and leaves: April-June, flowering head removal is effective. Removing flowering heads does not kill the plants; however it will help prevent seed dispersal. These actions will only be possible if SCG volunteers are willing and equipped with waders. 3) Repeated Mowing: May keep yellow‐flag iris contained and can potentially kill it by depleting the energy in the rhizomes after several years of intensive mowing. In SCG pond, this is only practical during times when the pond is dry (late July-early September). Effective Control methods –Yellow Flag Iris