LANDSCAPE WOOLLY THISTLE / ASTERACEAE Thistle is the common name of a group of flowering plants characterised by leaves with sharp prickles on the margins. Thistledown, a method of seed disposal by wind. The tiny seeds are a favorite of goldfinches and some other small birds. These slightly leaning trees are conical, though becoming broader when mature. -NATIVE BRITISH TREES by Andy Thompson © 2008-2010 chae young kim