When an almond tree keels over in a mature orchard, it could be a sign of something ominous. UC scientists are tracking a fungal infection in San Joaquin Valley almond trees that can cost farmers hundreds of thousands of dollars in lost production.

“Ganoderma's been around for a long time,” said Bob Johnson, a UC Davis graduate student who is leading the study for his doctoral thesis under the direction of UC Davis plant pathologist Dave Rizzo. “The tree failure we're seeing may be that we've now reached such a density of almonds here, that the problem just seems more widespread. Or it may be a new Ganoderma species in our...