A study conducted by scientists from UC Berkeley, UC Davis, UC Cooperative Extension and the U.S. Geological Survey found that since 1930, the density of large trees in California has decreased, reported John Fowler of KTVU News Channel 2.

The story said scientists compared exquisitely detailed tree data collected in the 1920s and 1930s with tree surveys made between 2001 and 2010. They identified significant and rapid changes in basic forest structure. As large tree density fell across the state, and the density of small trees increased.

"The thing that I think is particularly worrisome is how...