U.S.A., Oregon, Douglas, Myrtle Island Research Natural Area, 11.3-ha island in the Umpqua River, at the end of Cougar Creek Road, 7.3 km west of Bullock Bridge and OR 138.
Salix/Spiraea/Equisetum Community in rocky Riverwash soils bordering seasonal pools; associate: Cyperus esculentus