Shasta Knotweed
Polygonum shastense
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Shasta knotweed (left) with Kellogg's knotweed (Polygonum polygaloides ssp. kelloggii) observed along the Pacific Crest Trail #2000 on the south side of Cook and Green Mountain in northern Siskiyou County, CA, Klamath National Forest......July 14, 2020.
Paul Slichter