Tansy ragwort has long tormented rural landowners who graze livestock. Horses and cows are especially susceptible to this poisonous weed. In open fields, grazing animals will generally avoid eating tansy ragwort, but in heavily infested pastures they may have few other options. Contaminated hay is particularly a problem because it becomes impossible for feeding animals […]
Author Archive | Sam Leininger
This past season we have seen a rise in the number of Oblong spurge (Euphorbia oblongata) sites appearing in Clackamas County. Oblong spurge is a class A noxious weed in the state of Oregon, and eradication of this species is required across the state. It is known to be highly aggressive and can displace native […]
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 […]
Summer is here and the weeds and wildflowers are blooming all around us. With the burst of summer color, come the many bees, flies, beetles, moths, and butterflies that serve to pollinate these plants. Pollinators are vitally important to the health of our natural areas and local economies. Invasive weeds can play an important role […]
If you own livestock, now is the perfect time to secure your forage for the year. Hay production is at its peak, and there are lots of producers with ample supply. When purchasing hay it is important to consider the potential for introducing weeds through contaminated hay. One strategy to reduce the risk is to […]
The WeedWise Program has finalized Best Management Practices for controlling Garlic mustard. Check out this comprehensive guide today.
Where do you start when you are dealing with 20 acres of pasture land heavily infested with Blessed milkthistle? The first step is to call the WeedWise program! We were recently contacted by a landowner with this impressive stand of Blessed milkthistle (Silybum marianum) growing in horse pasture lands. The landowner was feeling very overwhelmed […]
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 […]
Tired of all the complicated jargon? We’ve added a resource to help. Check our growing glossary of terms and acronyms.
The WeedWise Program has finalized Best Management Practices for controlling Himalayan blackberry. Check out this comprehensive guide today.