Why do so many ornamentals ESCAPE?

Many noxious weeds are, in fact, escaped garden plants. Some escaped plants are temporary wanderers outside our care and nurturing, some only occupy niches where nothing else wants to grow. Some, however, become ecological bullies, crowd out native plants, poison livestock, and damage local ecosystems.

Qualities of Common Ornamental Plants

  • Establish rapidly
  • Grow fast
  • Mature quickly
  • Abundant flowers
  • Adapted to environment
  • Free of major insect or disease problems
  • Easy to propagate

Characteristics of Noxious Weeds

  • Establish rapidly
  • Grow fast
  • Mature quickly
  • Prolific seed producers
  • Adapted or adapt quickly to environment
  • No natural predators or diseases to keep populations in check
  • Produce abundant propagules

How you can help

  • Choose native plants where possible, and to add color and diversity to your garden, choose plants with a long standing reputation for being well-behaved. For some great alternatives to invasive ornamentals check out:
  • Avoid wildflower seed mixtures. Instead, choose flower and grass seed individually from the well-behaved plant lists and mix your own.
  • Remove spent flower heads from plants such as butterfly bush.  Bag and dispose of them with trash rather than compost or yard waste.
  • Watch for and remove any volunteer seedlings that may emerge.
  • Report sightings of ESCAPED plants on our monitor list. Knowing where and how wide spread escaped plants are helps us determine what plants we need to be most concerned about.


Have you seen any of these plants on a roadside, hillside, by a river or stream? Have you seen them in a ditch or forested area?  Chances are pretty good that they have escaped cultivation.We are currently monitoring for these species.


Arundo Donax Arundo donax, also known as “Giant Reed”, is a tall, erect perennial grass.  It can look a lot like a rather leafy bamboo, and grows to heights of 20-30 feet when established.  It may have green or variegated leaves.  Arundo spreads by underground rhizomes, forming dense stands.  Where it has escaped cultivation (California and much of the southern United States), Arundo has developed large, difficult to control infestations, and is a very serious fire hazard.
Garlic Mustard Garlic Mustard, one of the fastest spreading invaders in woodland habitats of North America. Up to 3 feet tall with triangular to kidney shaped leaves and small white flowers clustered at tops of stems. Roots and new leaves smell like garlic in the spring.
Oregon Public Broadcasting Television Presentation:Invasive Species Rapid Response


Please remember to report plants in locations where they wouldn't have been planted intentionally.
Thank you!

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Washington State Noxious Weed Control Board Monitor List

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