The newest issue of the journal "California Agriculture" (April-June 2013) published by the University of California  and UC Division of Agriculture and Natural Resources just came out and has two articles written by UC weed researchers

Check out the whole issue here or the specific articles at the links below.

For switchgrass cultivated as biofuel in California, invasiveness limited by several steps
by Joseph M. DiTomaso, Jacob N. Barney, J. Jeremiah Mann, and Guy Kyser             

Stinkwort is rapidly expanding its range in California
by Rachel Brownsey, Guy B. Kyser, and Joseph M. DiTomaso