Prison inmate Kevin Black, 54, who is in the last 90 days of an eleven-year sentence, clears the path to lay water pipes outside Oak Glen Conservation Fire Camp #35 in Yucaipa, California November 6, 2014. Black is among thousands of convicted felons who form the backbone of California's wildfire protection force under a unique and little-known prison labor program. But California may soon find it harder to recruit new inmate firefighters after a ballot measure was passed last month to ease prison crowding by reducing felony sentences to misdemeanor jail terms for most non-violent, low-level offenses, including many drug crimes. That measure will likely diminish the very segment of the inmate population that the California Department of Forestry and Fire Protection, or Cal Fire, draws upon to fill its wildland firefighting crews. Picture taken November 6. To match Feature USA-FIREFIGHTERS/CALIFORNIA REUTERS/Lucy Nicholson (UNITED STATES - Tags: CRIME LAW SOCIETY)