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2019-09-06: Our discovery of this thistle species, now thought to be Carduus cinereus, was not as early an early a detection as one would like.  It also took us all a while to recognize it as something different from Italian thistle (Carduus pycnocephalus) after that.  The plant has limited windows of visibility and exists in some of the most rugged and remote country we have in Oregon. It is super rough country to access. This site is almost a 20 mile ride into back country, or a 3 hour drive plus an hour jet boat ride plus a 5-mile hike. It is much easier to have horses and mules carry you and your gear in to treat these sites. Add in complex NEPA considerations over time, low weed control budgets locally, and there is much left to do.  

What has also happened is all the work that it took to figure out the conundrum of its identification. Thanks so much to John Gaskin for keeping that effort alive!  

Our delimitation surveys have given us a pretty fair idea of where the plant is (on the Oregon side).  We did release Trichosirocalus horridus, a root crown weevil, on it -- though they don’t appear to have established and may not be appropriate for the plant.  Some treatments in Hells Canyon of outlying and vector sites have also occurred.  


progress report shared by

Mark Porter and Shawna Batista

Turkish thistle infestation in OregonTurkish Thistle (Carduus cinereus) infestation in Hell's Canyon, Oregon

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