The first step in correcting a garden problem is to identify the cause. Many problems are caused by insects, fungi, diseases, various mammals, birds, etc. Other problems are caused by incorrect cultural practices, such as too much or too little water, too much or too little fertilizer, poor soil, etc.
If you need help in identifying the cause(s) of your garden problem, you can describe the problem, take pictures of the damage if possible, and email this information to our Hotline. We may be able to identify the cause(s) and steer you in the correct direction. If there appear to be problems with cultural practices, we can advise you as to your best course of action. We may also suggest that you submit samples to the Agricultural Commissioner for their free identification service.
Common Pest Problems
If you are sure that you already know what the cause is, you can consult our Pest Notes which describe the damage caused and how to manage it. Pest Notes are peer-reviewed UC Davis publications about specific pests, including insects, fungi, mammals, birds, diseases, and even weeds, as well as pest management topics. Pest Notes are available for most of the common pests that have been around for awhile.
Pest Notes are directed at California's home and landscape audiences. They are available in either a web (HTML) version or a PDF version. The web versions include color photographs and links to other pages on our web site. The PDF versions have been designed specifically to print and photocopy well in black and white, and usually have line drawings instead of color photographs. Although they look substantially different from one another, the text is identical in both versions.
Visit the Pest Note Index to see if your problem is covered.
Exotic Pest Problems
If there is no Pest Note covering the problem you have identified, it is possible that you have an exotic pest. A new exotic pest appears in California every 60 days. Such a species may not be a problem in its native habitat because other organisms have evolved to feed on them, keeping their populations under natural control. These pests usually arrive without their natural enemies. Without natural enemies to feed on them and keep them under control, they can rapidly become a problem, until researchers and regulatory agencies learn how to control them.
If you find an unusual pest in your garden, visit the Exotic Pest Index. This website contains information on recently introduced pests for which there is no Pest Note. You can find out what progress has been made on managing the pest.