Policeman’s helmet (Impatiens glandulifera) is an invasive weed which grows in ditches, wetlands, and along waterways. Native to India, this fast-growing annual was introduced as a ornamental plant due to its impressive growth and the showy purple, pink or white blooms. Since introduction, it has escaped cultivation to become the dominate riparian vegetation in many […]
Orange hawkweed (Hieracium aurantiacum) is a relatively new invasive weed in Clackamas County. With your help, our team plans to keep it from becoming a common problem for landowners! A member of the sunflower family, orange hawkweed is native to central and southern Europe and grows in open areas like gravel pits, roadsides, meadows, pastures, […]
Garlic mustard (Alliaria petiolata) is an increasingly invasive weed in our community. Native to central and western Europe, this fast-growing plant commonly invades sites such as parks, trails, roadsides, and streamsides. April is a great time to manage this priority invasive weed on your property. Sometimes referred to as Jack-by-the-hedge, garlic mustard is easily identified […]
February is the one month of the year that many of us associate with our love and romance. We cut out paper hearts for Valentine’s Day cards and wrap up cut flowers for that special person in our lives. But there is another reason to celebrate because February 14th also Oregon’s birthday! Way back in […]
Its October, and that means its time for a new Weed of the Month! We are working with our partners at the Columbia Gorge Cooperative Weed Management Area to promote invasive Italian arum (Arum italicum) as our weed-of-the-month for October. Italian Arum, also known as “orange candleflower” and “Italian lords and ladies,” is a non-native […]
Its September, and that means its time for a new Weed of the Month! We are working with our partners at the Columbia Gorge Cooperative Weed Management Area to promote invasive knotweeds (Fallopia sp.) as our weed-of-the-month for September. Knotweed is a horribly invasive plant unleashed on the countryside by well-intentioned gardeners attracted to its […]
Its August, and that means its time for a new Weed of the Month! We are working with our partners at the Columbia Gorge Cooperative Weed Management Area to promote Puncturevine (Tribulus terrestris) as our weed-of-the-month for August. Puncturevine is a sprawling annual plant that forms a dense mat with very sharp, spiny seed heads. […]
We are once again partnering with our friends from the Columbia Gorge Cooperative Weed Management Area to feature invasive knapweeds as the target weed for the month of July. Clackamas County has many kinds of knapweed, but the three most commonly found in our area are Spotted, Diffuse and Meadow. Although slightly different, they all […]
Its June, and that means its time for a new Weed of the Month! We are working with our partners at the Columbia Gorge Cooperative Weed Management Area to promote Scotch Broom (Cytisus scoparius) as our weed-of-the-month for June. Scotch broom was introduced as an ornamental along highway corridors and in western Oregon as a […]
