If you have eucalyptus trees, you might have noticed white, crusty growth on the leaves. Or maybe you saw a sticky, blackened mess of fallen leaves under a eucalyptus tree. These are signs of the redgum lerp psyllid, one of the most common psyllid pests that damages eucalyptus trees in California.

The adult psyllid is very small and as nymphs, they are concealed under a waxy cap, or lerp. As they feed, they excrete honeydew which can lead to the growth of black sooty mold, the source of those sticky leaves under the tree.

Although under biological control in coastal areas, this pest is still a problem under some growing conditions and on specific Eucalyptus species. Cultural practices to manage...

Woodpeckers are well known, colorful birds often found in wooded neighborhoods and forested areas. While they are wild creatures many people appreciate, they can become a pest problem when they damage buildings in search of food and nest building materials, or a nuisance pest with their rhythmic drumming.

Both male and female woodpeckers drum with their beaks to proclaim their breeding behavior and social dominance. Their pecking can cause structural damage, leaving gaps and holes in wood as they search for insects. Acorn woodpeckers create or find holes in buildings, fence posts, and utility poles to store acorns. Woodpeckers can also damage trees when they remove the bark to access the insects hiding underneath.

But...

All mistletoes infest and grow as parasites on trees and large shrubs. In some cases, the host plant can be severely damaged. But recent studies have shown that broadleaf mistletoes can shelter and feed wildlife, including birds and small mammals. So, mistletoes are both parasitic plants and bird food!

Because mistletoes can damage trees, you may decide to do something about mistletoes infesting your trees. The first step is to find out whether you're dealing with broadleaf or dwarf mistletoe. Mistletoes differ in their life cycles, the damage they cause and management methods. UC Cooperative Extension Advisors Igor Lacan (San Mateo and San Francisco Counties), Steven Swain (Marin County) and Ed Perry (Stanislaus County,...

Recent wet weather in many parts of the state has spurred emergence of winter weeds. How these weeds are managed varies by the type of weed and where it's growing. In IPM, identification is always the first step toward effective pest management. A few common weeds you may be seeing in your garden or landscape now are profiled below.

Oxalis

Also known as Bermuda buttercup, buttercup oxalis, or sourgrass, this weed grows throughout California's coastal and inland landscapes. It can be a weed in lawns, flowerbeds, groundcovers, and shruby areas around the home. It has an upright growth with 3 heart-shaped leaflets and produces bright yellow flowers in late winter or early spring. See