Wildfires and Climate Change: Southerly Plants Pushed North

The southwest is moving northward, pushed there by California wildfires, as researchers from University of California, Davis recently reported in the Journal of Ecology.

That is, as fires burn forest understories, the plants that grow in their place are increasingly those normally found in more southern parts of the West. "The plants we're finding underneath our forests are becoming more like those seen in Mexico and Southern California," said lead author Jens Stevens, a postdoctoral scholar with UC Davis, in a release. "Under climate change, we're seeing species from drier, warmer areas increasingly taking over. It's a long process, but forest disturbance, be it thinning or wildfire, has the potential to hasten those shifts."

This can be a startling change: A forest floor normally strewn with lupine and violets, typical of Northern California and Canada--may now be manzanita and monkey flower, or other foliage normally found to the south, a release noted.

That said, in a vote for controlled thinning and burns, some cooler microclimate remain in forests that were thinned before a fire and therefore burned less hot and left more tree canopy, the release said.

The study looked at 12 different mixed-conifer sites in California. These were from Modoc to San Bernardino counties and included Sierra sites. The areas burned by the Angora Fire in 2007 and the American River Complex areas northeast of Sacramento burned in 2008 were included, for instance, the release noted.