Tall Goldenrod (Solidago altissima) 7/21/12 David, D&M MD

-hairy stems
-3 veins in leaves
-toothed leaves
(leaves most likely with fine teeth, and if toothed then near ends of leaves, stems green, flower heads pyramidal)

Tall Goldenrod (Solidago altissima) - scientific description:
http://www.nttlphoto.com/botany/asters-goldenrods/Goldenrods/Solidago/Altissima/s_altissima.htm
"-Leaf and stem coloration of this species often appears as gray-green or dull green due to dense pubescence.
-Colony-forming from rhizomes." ...more at link

description:
http://www.missouriplants.com/Yellowalt/Solidago_altissima_page.html
"This species is in the group of tall Goldenrods which includes other similar species like S. gigantea Ait. and S. canadensis L.. These species have no basal rosettes at anthesis and have leaves which are largest in the central portion of the stem but are typically all similar in size." ...more at link