BARNS: When the historic hay barn at B Ranch blew down during a storm on March 5, two cows died. "It was just a tired old barn," rancher Jarrod Mendoza said. "The barn saw a lot of storms, and this was its last one." A retired employee for the National Park Service, Dan Brown, will give a presentation on his work preserving barns in the Point Reyes National Seashore during the Marin Conservation League's Agricultural Land-Use Committee on Friday, April 22.   David Briggs