pBy Laura Zuckerman/ppSALMON, Idaho (Reuters) - It took less than an hour last month for a Montana wildfire to reduce Scott McRaes ranch to thousands of blackened acres devoid of the grasses that were to sustain hundreds of cattle./ppThat is 500 mouths to feed with nothing to eat in sight, said McRae, 53, co-owner of a family ranch founded in the 1880s in southeastern Montana./ppMcRae is among scores of ranchers across the U.S. a href=http://www.scientificamerican.com/article.cfm?id=ravaged-by-fires-western-ranchers[More]/a