If you start looking around Clackamas County, it won’t take you long to find the invasive tree-of-heaven (Ailanthus altissima). This state-listed noxious weed is increasingly common in many of our urban areas where […]
Tag Archives | invasive weeds
October Invasive Weed of the Month: Himalayan Blackberry
Himalayan blackberry (Rubus bifrons) tantalizes us with its sweet fruits in the summer and tortures us with its prickly vines all year long. Also known as Armenian Blackberry, this wide-spread and aggressive weed […]
July Invasive Weed of the Month: Tansy Ragwort
Tansy ragwort (Senecio jacobaea) is an invasive weed with a long and deadly history in the Pacific Northwest. In Oregon, it is designated as a Class B invasive weed. It is believed to […]
Tansy Poisons Livestock – and Neighborly Relationships!
Tansy ragwort (Jacobaea vulgaris) has long tormented hay producers and rural landowners who graze livestock. Horses and cows are especially susceptible to this poisonous weed. In open fields, grazing animals will generally avoid […]
Clean Your Boots to Protect Our Natural Areas
Clean your boots! And your sneakers, sandals, and flip-flops too. Give them a quick check before and after you hike to prevent the spread of invasive weeds. Summer is here and that means […]
National Invasive Species Awareness Week, May 15 – 22
What’s better that one National Invasive Species Awareness Week for 2021? How about two? National Invasive Species Awareness Week Part 2 (May 15 – 22, 2021) is upon us! Take some time this […]
April Invasive Weed of the Month: Garlic Mustard
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 […]
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 many native thistles found in Oregon, Canada thistle can quickly overrun an area and displace native […]
National Invasive Species Awareness Week: February 22 – 26
National Invasive Species Awareness Week (February 22 -26, 2021) kicks off today! Once a year, folks from around the country take a full week to consider the many impacts that non-native invasive species […]
