San Antonio Express-News: Area farmers and ranchers don’t need a color-coded map or a gloomy weather report to know they’re at ground zero of what is becoming one of Texas’ worst droughts ever. They see it daily in parched fields too dry for seeds to sprout; in stock tanks that carried water during the legendary drought of the 1950s but now are cracked and dry; in prickly pear cactus so thin that they don’t provide much moisture when their needles are burned off for skinny cows to enjoy. Even some of …