Also known as: Parrot feather, parrot’s feather, parrotfeather water milfoil, Brazilian water milfoil, water-feather
Parrotfeather’s vibrant leaves make it an appealing addition to any backyard pond or water feature, but it can drastically alter natural aquatic ecosystems. Once parrotfeather has escaped cultivation, if forms dense mats that shade out native aquatic plants and inhibits water flow and recreation.
Description:
| Life Cycle: | Perennial (life cycle lasts more than one year) |
| Early Detection and Rapid Response species: | Yes |
| Height: | Stems can grow 15 feet long (5 meters) |
| Leaf Description: | Feather-like leaves are arranged in whorls An arrangement of leaves that radiate from a single point and wrap around the plant’s stem.. Above water leaves are bright green and resemble small fir trees. Submerged leaves are darker green. |
| Fruit & Flower Description: | Small, while flowers can be found on above water stems. It has male and female plants, meaning that both plants are needed to create viable seeds. |
| Bloom Time: | Spring |
Habitat:
- Can be found in freshwater ponds, streams, and lakes.
- It thrives in areas with slow moving or still water rather than fast moving water.
- The above water stems are well adapted to water level changes and can survive on the banks river and lake shores.
Impact:
- Parrotfeather forms dense mats that cover the surface of freshwater ponds, streams, and lakes.
- Its dense mats block sunlight from native aquatic species, leading to a monocultures Growing a single crop or plant..
- When the dense mats die back, their decomposition reduce oxygen levels in water and create “dead zones” in the water.
- Heavy infestations can clog waterways, slowing streams and impeding boat traffic.
What we’re doing about it:
- Parrotfeather is a priority species for the Tualatin SWCD. As such, our Invasive Species Program has been actively monitoring and treating it throughout the watershed.
- If identified within Washington County, a specially trained crew can come out survey for parrotfeather. If found, the crew will treat the infestation for free.
What you can do about it:
- If you think you’ve found parrotfeather anywhere in Oregon, please report it to the Oregon Invasive Species Hotline.
- Parrotfeather can be difficult to control since it can sprout from small fragments. It is best to wait until the water level has dropped, usually mid-summer, before attempting to remove by hand or rake. Once removed, all plant material should be thrown away in a plastic bag in the trash.
Look-alikes:
Hornwort (Ceratophyllum demersum), a native aquatic perennial, can be found in the same habitats as parrotfeather. Its light green and feathery appearance make it easy to mistake for parrotfeather. Hornwort’s leaves are forked, not feathery like parrotfeather’s.
Parrotfeather loos like another invasive aquatic species, Eurasian watermilfoil (Myriophyllum spicatum). This plants are difficult to tell apart, but Eurasian watermilfoil blooms above water, while parrotfeather blooms underwater.
Noxious Weed Listing:
| State of Oregon: | Class B |
| State of Washington: | Class B |
More Resources:
Download the Parrotfeather Best Management Practices Factsheet
- University of California, Weed Research & Information Center: Parrotfeather