Description: English: Stem of Joe Pye weed (
Eutrochium fistulosum) showing the
fistula or hollow from which the plant takes its latin name. The hollow is lined with
pith and higher in the stem (shown to the right) the pith completely fills the stem. The plant was collected in
Iowa City, Iowa and photographed the same day. Date: 16 July 2014, 18:51:20. Source: Own work. Author:
Douglas W. Jones.