Noxious Weeds List
The following is a list of species known to be present or have the potential to infest Thurston County. It is approved and updated annually by the Thurston County Weed Board.
Noxious Weed Classifications
• species new to the state
• limited distribution throughout state
• goal is to eliminate before established
• landowners required to control
• widespread in parts of state, limited or absent in other parts of the state
• goal is to prevent spread into new areas and contain or reduce existing populations
• the state designates Class B noxious weeds in certain areas
• a county weed board may select Class B noxious weeds for control in the county
• landowners required to control Class B designate and Class B select noxious weeds
• control of all other Class B noxious weeds not required but recommended
• often widespread, or of special interest to agriculture
• a county weed board may select a Class C non-designate for control if it is considered a local priority
• control of all other Class C noxious weeds not required but recommended
Noxious Weeds Fact Sheets
Scientific Name | Egeria densa - Fact sheet awaiting approval
except variety, azoricum
Scientific Name | Foeniculum vulgare
(nonnative genotypes of)
Scentific Name | Phragmites australis
Scientific Name | Euphorbiaoblongata - Fact sheet awaiting approval
Scientific Name | Alliaria petiolate - Fact sheet awaiting approval
Scientific Name | Carex pendula - Fact sheet awaiting approval
Scentific Name | Carduus pycnocephalus -Fact sheet awaiting approval
Scientific Name | Ficaria verna - Fact sheet awaiting approval
Control is required in Township 18 N, Range 2W, Section 10 and on all transportation and utility rights of way, public land and gravel mines.
To be controlled on Thurston County property, gravel mines, heavy equipment storage areas and those rights of way that may directly or indirectly spread seed or contaminated material in wildlife refuges, nature preserves or other high quality habitat areas.
Scentific Name | Carduus tenuiflorus - Fact sheet awaiting approval
Control is required on transportation rights of way in all of Thurston County and on all other land except that portion of Thurston County East of Range 1 East and South of Township 17 North.
Control is required when 25 or more plants are present in an area of 20 acres or less. This area may include more than one parcel if the area is under the same ownership. Priority will be given to property in agricultural areas, particularly where livestock is present.
Scientific Name | Myriophyllum heterophyllum - Fact Sheet awaiting approval
Scientific Name | Hieracium murorum -Fact sheet awaiting approval
Scientific Name | Iris pseudacorus - Fact Sheet awaiting approval
Deep Lake, Lawrence Lake, transportation rights-of-way and Thurston County Property only
Scientific Name | Hieracium caespitosum - Fact sheet awaiting approval