Karen,
Here's a really nice route... but not in Santa Cruz Area
http://www.gmap-pedometer.com/?r=383623 it has hills, trees, and good spots to stop if necessary along with some climbing.
If you really want to ride in Santa Cruz; you can get a few routes on the south end of Santa Cruz county that are really nice (not many trees but decent roads) from this site...I've done the metric a couple of times.... not many places to stop so you'd need to be more self sufficient.
Tracy
ps. Try PMing Susie, she lives in Santa Cruz and might have more suggestions