Top Priorities

The Washington Invasive Species Council evaluated more than 700 invasive species in and around Washington to analyze which posed the greatest threat to the state’s environment, economy, and human health. The council selected 50 priority species for action in the short term.

To do the analysis, the council developed an assessment tool that evaluated each of the 50 species on their impact and ability to be prevented. The scores were plotted on the invasive species management priorities grid, which is being used as a management tool to guide council action.

It is important to note that there are many other groups doing important work with invasive species lists of their own. Some include only plants or aquatic species, some are specific to a region. The council’s statewide list represents the top threats from all categories of species – plants, animals, insects, algae, and pathogens.

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Asian carp	Atlantic salmon	Bark-boring moths	Brazilian elodea
Bullfrog	Butterfly bush	Caulerpa	Common crupina
Common reed (Phragmites)	Cordgrass (Spartina)	Dalmatian toadflax	Eurasian watermilfoil
European green crab	Exotic Apple Fruit Pests	Exotic leafrollers	Feral swine
Garlic mustard	Giant hogweed	Hawkweed	Himalayan blackberry
Hydrilla	Invasive crayfish	Japanese knotweed	Knapweeds
Kochia	Kudzu	Leafy spurge	Lymantriids
Marine clam	Mediterranean snail	Mitten crab	New Zealand mud snail
Northern snakehead	Nutria	Parrotfeather	Purple Loosestrife
Scotchbroom	Scotch thistle	Tamarix	Tansy ragwort
Tamarix	Tansy ragwort	Tunicates, non-native	Variable leaf milfoil
Viral hemorrhagic septicemia virus	Water chestnut	Wood-boring beetles	Yellow starthistle
Zebra and Quagga mussels