[Knotweeds: The Genus Polygonum in the Cascade Mountains of Oregon and Washington]
Prostrate Knotweed, Doorweed
Polygonum aviculare
The photo above and below show close-ups of
the leaves and flowers of prostrate knotweed as seen along road #82 at Snowking
Snowpark on the southern slopes of Mt. Adams..........October 2005. Note
that the outer and inner series of tepals in individual flowers are the same
length.
Paul Slichter