Policeman’s helmet (Impatiens glandulifera) is an invasive annual which threatens streams and rivers throughout the Pacific Northwest. It is designated as a Class B invasive weed in Oregon. This means that it is […]
Tag Archives | invasive weed
May Invasive Weed of the Month: Orange Hawkweed
Orange hawkweed (Hieracium aurantiacum) is a fairly new invasive weed in Clackamas County and, with your help, our WeedWise team plans to keep it from becoming a common problem for landowners! A member […]
The Undesirable Beauty of Lesser Celandine
Each spring we welcome the return of abundant flowers and cherish them as they lift our spirits. Unfortunately, some of these beautiful plants have proven to be aggressive and, ultimately, highly unwanted. One […]
March Invasive Weed of the Month: Canada Thistle
Canada thistle (Cirsium arvense) is a wide-spread invasive weed found in all parts of Clackamas County. Unlike the many native thistles found in Oregon, Canada thistle can quickly overrun an area and displace […]
December Invasive Weed of the Month: English Holly
English holly (Ilex aquifolium) is a popular evergreen frequently noticed during the month of December when festive decorators “deck the halls with boughs of holly”. For many people, the shiny, dark green leaves […]
November Invasive Weed of the Month: Spurge Laurel
Spurge laurel (Daphne laureola) is neither a spurge nor a laurel, but rather an invasive plant in the Daphne family. This perennial plant has poisonous berries, spreads aggressively in our native forests, and […]
August Invasive Weed of the Month: Puncturevine
Puncturevine (Tribulus terrestris) is aptly named! This invasive weed has spiny seed heads on it that can easily puncture a bike tire, inflatable raft, animal paw, or footwear. Be on the lookout because […]
June Invasive Weed of the Month: Policeman’s Helmet
Policeman’s helmet (Impatiens glandulifera) is an invasive annual which threatens streams and rivers throughout the Pacific Northwest. It is designated as a Class B invasive weed in Oregon. This means that it is […]
January Invasive Weed of the Month: English Ivy
English ivy (Hedera helix) may conjure up images of cozy, country cottages, but don’t be deceived. This invasive weed can destroy buildings, poison pets, and topple trees. The very characteristics that made it […]
