What was done
The authors analyzed the results of 28 experiments conducted over the past decade to determine the range of responses of Poplar (Populus) trees to atmospheric CO2 enrichment.  Their review is especially important, for poplar trees are predicted to play an increasing role in wood production and carbon sequestration within managed tree plantations as time progresses.

What was learned
Elevated CO2 increased rates of net photosynthesis in 74% of the reviewed studies.  Some of the non-responsive observations were made late in the growing season when senescence was occurring.  The CO2-induced increases in photosynthesis led to increases in total biomass ranging from 22 to 90% and averaging 33%, in spite of the fact that several of the studies were performed when environmental stresses and resource limitations made growing conditions less-than-optimal for this genus.  In addition, elevated CO2 reduced stomatal conductance and water loss in the majority of studies.

What it means
As the air's CO2 content continues to rise, poplar trees will likely exhibit increases in growth that will shorten the time from planting to harvest and enhance their importance in the agro-forestry market.  Also, with greater productivity and biomass production, significantly more carbon will be sequestered within the woody components of poplar trees and the soils in which they grow, helping to slow the rate of rise of the air's CO2 content.  Thus, the use of Populus species in managed tree plantations would appear to be a promising and prudent cultural practice for future foresters.