What a difference a year makes It was one year ago that we reported a large infestation of milkthistle (Silybum marianum) growing in a twenty-acre horse pasture outside of Wilsonville. At that time, the WeedWise program was approached by the resident for assistance in helping her to control the milkthistle. As a priority invasive weed […]
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Think twice before killing those thistles: Thistle Identification
Thistles are one of the most common weed problems that property owners deal with in Clackamas County. Many of the thistles we encounter are invasive and can grow to dominate a property. But did you know there are at least four thistles that are not only non-invasive, but native to western Oregon? These native thistles […]