Resources:

http://www.tcweed.org/Weeds/WeedID.html

http://www.mda.state.mn.us/plants/badplants/leafyspurge.htm

http://www.fsu.edu/~imsp/silent_invaders/new_weeds/main_html/

http://www.mtweed.org/weed_leafy.html

http://www.cwma.org/nx_plants/leafspurge.htm