This page is under construction. Here are some links to short articles about seasonal pests:
Asian Woolly Hackberry Aphid--a new pest in the Sacramento Valley
Dormant spraying of fruit trees
Codling Moth --the worm in apples, pears, and other fruit and nut trees.
Plant diseases in the spring
Check out UC Davis' great Integrated Pest Management website for lots of information.
Entomologist and rosarian Baldo Villegas has a very informative website with lots of great pictures: