Conservationists often place the greatest value on protecting large contiguous habitat areas. However, as two new studies (here and here) in the journal Biological Conservation show, single, isolated trees on agricultural lands can give a big boost to bird and bat species. According to the second study,

"Our results suggest that oak savanna restoration in agricultural systems does not necessarily need to be an all-or-nothing proposition. Large savanna-form oak trees scattered in agricultural fields have wildlife value, particularly for many oak-associated birds. Moreover, individual trees have a relatively small physical footprint thus allowing minimal impact on agricultural production and contributing to biological diversity at a small cost to production." 

A 3,000-year record from 52 of the world's oldest trees shows that California's western Sierra Nevada was droughty and often fiery from 800 to 1300, according to new research. The health of the giant sequoia forests seems to require those frequent, low-intensity fires, Thomas W. Swetnam said. He added that as the climate warms, carefully reintroducing low-intensity fires at frequencies similar to those of the Medieval Warm Period may be crucial for the survival of those magnificent forests.