Additions to 2013 Weed List
The
Washington State Noxious Weed Board adopted the 2013 State Noxious Weed List at
their November 7, 2012 meeting. The 2013 list includes a number of
changes from 2012, including a few new species. All of the changes are
detailed on the “What’s New” page of the Washington State Noxious Weed
Board website http://www.nwcb.wa.gov/. Some of the new weed additions include:
French broom, Genista
monspessulana, as a Class A noxious weed. French
broom is an invasive shrub with green, ridged stems, small, three-parted leaves
covered in fine hairs, and bright yellow, fragrant flowers. Currently listed as
a noxious weed in Oregon, California, and Hawaii, French broom spreads rapidly
and displaces native vegetation. Climate change seems to be expanding its
range. Once used as an ornamental plant, it does not appear to be sold through
the horticultural industry anymore. To the best of our knowledge, there is only
one known escaped population of French broom on the University of Washington
campus. A Class A listing would mean that all known French broom populations
would need to be eradicated.
Tall hawkweed, Hieracium
piloselloides, as a Class B noxious weed. Tall
hawkweed is a non-native, perennial plant that has been found growing in
Washington State. Presently, it appears to have limited distribution in
Washington although more populations may exist due to the difficulty of
differentiating between Hieracium species. Hieracium species in
general can be fast growers, invading a variety of habitats, and out compete
native and desirable plants.
Common teasel, Dipsacus fullonum,
as a Class C noxious weed. Common teasel is a monocarpic
herbaceous plant that has been a common weed of roadsides and other disturbed
areas and recently has begun to invade valuable agricultural lands in
Washington. Due to the present management practice of mowing, common teasel seed
heads that contain viable seed are being spread widely along roadways and into
various habitats. Listing common teasel as a Class C noxious weed will allow
county noxious weed control boards the option of selecting this plant for mandatory
control at the local level.