favicongohere
Invasive Species in Amherst State Park
Iris pseudacorus - Yellow Flag Iris, Yellow Iris, Water Flag, Yellow Flag
Close up Photo
photo by WNY PRISM
June 5, 2015
Infestation Photo
photo by WNY PRISM
June 5, 2015
Yellow Flag Iris (Iris pseudacorus) is a perennial native to Europe, eastern Asia, and northern Africa with bright yellow flowers on a robust stalk, often over-topped by long, stiff, sword-like leaves in clumps. It is in the family Iris and flowers in the months June through August.. Yellow Flag Iris invades wetlands, riparian habitats by producing dense monocultures that outcompete native vegetation. This plant is found growing in several spots along Ellicott Creek.
Smaller patches of yellow flag iris can be dug out of the soil using shovels, but care must be taken to remove the entire root mass and to properly dispose of material, similar to Japanese knotweed. Repeated mowing for several years may suppress patches of yellow flag iris and deplete the plant’s energy. However, mowing may be difficult due to the fact that yellow flag iris prefers wet habitats. Take caution when removing yellow flag iris, by wearing gloves, long sleeves and pants, as the resins from the plant may be a skin irritant.
It would be valuable to educate the public about yellow iris. Yellow flag iris is a prohibited species in New York State, though it is a popular plant in water gardens and many members of the public do not understand that it is an invasive species.