Behind plot is a narrow scoured floodplain forest on cobble, then a mowed picnic area. Upstream along slower reach is a weedier cobble zone with scattered Bidens, not so much dogbane.;Depostional bar along a flashy river, across from a steep slope and along a rapid. Substrate are rounded cobbles averaging 1-4 dm long piled in a levee along the channel edge, with a lower dry back channel. Site is frequently flooded, preventing tree establishment. Vegetation is an herbaceous community dominated by dogbane.
Representativeness
Small patch of cobble bar dominated in late summer by Apocynum cannabinum.