The summer is winding down, but many warm-weather pests, like whiteflies are still going strong. Whiteflies are tiny white insects commonly found in vegetable garden and landscape plantings in large numbers. Often they fly around plants when disturbed, which is when people first notice them.

Despite their name, whiteflies are not true flies but are actually related to aphids, scales and mealybugs. Like these insects, whiteflies cause damage when they suck plant juices from leaves, which yellow or die off. Whiteflies excrete excess liquid called honeydew that is sticky, and may be covered with black sooty mold. The honeydew also attracts ants, which disrupt naturally-occurring

This summer, the media frequently reported an increase in the density of pests in the home and landscape. The drought has been cited as the cause of these problems. Pest control companies quoted in articles confirm that the demand for their services is much higher this year than in years past.

Many people are asking, “Why are there so many more pests this year than usual?” According to Dr. Andrew Sutherland, the urban Integrated Pest Management Advisor for the San Francisco Bay Area, we are asking the wrong question. “The overall abundance of pests probably hasn't changed and may even have decreased as compared to wet years. The real questions we should be asking are ‘Why are these pests appearing earlier...

Weeds don't just look unsightly, they also rob other plants of water, says a UC Agriculture and Natural Resources (UC ANR) expert in a new water conservation video released today.

Any loss of water is a concern as California's fourth summer of drought comes to a close. Missy Gable, director of the UC Master Gardener Program, suggests removing weeds so they won't compete with ornamental plants or edible vegetables.

If weeds are scattered throughout your yard and mixed in with plants, hand-weeding is probably the best eradication method. Cultivation can damage ornamentals with shallow roots, bring weed seeds to...

[From the August 2015 issue of the UC IPM Green Bulletin]

Although pine trees are comparatively drought tolerant, there comes a point where even hardy trees become stressed by lack of water. Stressed pines frequently exhibit symptoms such as thin, slightly yellowish canopies, or roots that "spider" across lawns (Figure 1). By the time pine trees begin turning brown, they are usually dying, but with some precautions, many trees can be saved before they reach this point.

California has a number of native bark beetle species that individually do only minor damage as they...