The State of California is banking on its forests to help reduce planet-warming carbon dioxide in the atmosphere. But that element of the state's climate-change solution arsenal may be in jeopardy, as new research from the University of California, Irvine reports that trees in California's mountain ranges and open spaces are dying from wildfires and other pressures -- and fewer new trees are filling the void.

"The forests are not keeping up with these large fires," said study co-author James Randerson, the Ralph J. and Carol M. Cicerone Professor of Earth system science at UCI. Across the entire state, tree cover area has declined 6.7 percent since 1985. "These are big changes in less than four decades," he said.