The following list includes the scientific and common names of noxious weeds found in the county that are also listed by the Skagit County Noxious Weed Control Board as of 1999. This list is a subset of the Washington State noxious weed list. Control and eradication is required statewide. Class B Designate Noxious Weeds are those whose populations within a region are such that all seed production can be prevented within a calendar year.
Control is required in Skagit County.
Class B Noxious Weeds pose a serious environmental or economic threat, are not native to the state, and are of limited distribution within a limited region or area. County weed boards decide which will be controlled. Class C Noxious Weeds include any other noxious weeds. County weed boards decide which to control. Lysimachia vulgaris Lythrum salicaria Lythrum virgatum Cyperus esculentus Myriophyllum aquaticum Lepidium latifolium Impatiens glandulifera Tribulus terrestris Eruca vesicaria ssp.