If you are interested in the molecular makeup and study of hybrid poplars these links will take you to some interesting places in the net that study those trees. This is only a sample, there are many other HP sites around.
Alberta
Pacific Forest Industries
Boise
Cascade Corporation
Champion
International Corporation
Union
Camp Corporation
Electric
Power Research Institute
Westvaco
Corporation
Fort
James Corporation
Weyerhaeuser
Company
Georgia-Pacific
West, Inc.
British
Columbia Ministry of Forests Research Branch
Washington
State University
Tree Biologist on call!. When stumpped for answers, ask John!
See a good long term plan to manage a poplar plantation