- Author: UC IPM
A single gopher can destroy a landscape quickly, so control measures need to begin as soon as the gopher is detected. Mounds of fresh soil are usually the first indication of their presence. Effective integrated management of pocket gophers relies largely on exclusion measures and trapping, although poison baits are also available.
Read more about gophers, their behavior, and management in UC IPM's newly updated Pest Notes: Pocket Gophers, by Dr. Roger Baldwin, University of California Cooperative Extension Specialist in Human-Wildlife Conflict Resolution.
- Author: UC IPM
Peach leaf curl is a disease that affects peach and nectarine trees. Although you may not see symptoms right now in the dormant season in California, it's time to think about treatment, especially if your tree had the disease last year.
Symptoms of this fungal disease include distortion, thickening, and reddening of foliage as trees leaf out in the spring. As weather warms, damaged leaves that die and fall off trees are replaced with new, usually healthy leaves. However, after several years without treatment, peach leaf curl will cause tree decline and reduced fruit production.
Avoid peach leaf curl by growing varieties resistant to the disease. For nonresistant peach and nectarine trees, consider spraying with preventive fungicides in the dormant season just before or as buds swell.
See the UC IPM publication Pest Notes: Peach Leaf Curl for more information about the disease and management options. Always read and carefully follow all precautions and safety recommendations given on the pesticide label.
- Author: Elaine Lander
[From Pests in the Urban Landscape blog]
Mistletoe is a familiar sight of the season, often found wrapped in ribbon and hung for certain festivities this time of year. But did you know it is actually a parasitic plant that grows on a number of landscape trees in California?
There are two types of mistletoe in California. Broadleaf mistletoes attack certain broadleaf trees and some conifers, while dwarf mistletoes attacks only conifers. Broadleaf mistletoes have green stems with thick, oval leaves. Dwarf mistletoes are smaller, with short stems and yellow, scaly leaves.
Both types of mistletoe grow through tree bark and into the tree's tissue, living off the host tree. Healthy trees can typically tolerate a few mistletoe infections although individual branches may be weakened by the parasite. Trees with a heavy infestation can be stunted or even killed if they are stressed by drought or disease.
What can be done about unwelcome mistletoe? The most effective way to control mistletoe and prevent its spread is to prune out infected branches as soon as possible. If mistletoe is infecting a major branch or trunk, you can cut off the mistletoe and wrap the area to exclude light. See our Pest Notes: Mistletoe for additional instructions.
Reducing mistletoe is a community effort since it spreads easily from tree to tree. So if you find yourself underneath some mistletoe this season, be sure to share this information with your neighbor!
/span>- Author: Denise Godbout-Avant
Aphids
According to UC Integrated Pest Management (UC IPM), aphids are small, soft pear-shaped bodied insects with long legs and antennae, with slender mouthparts used to pierce stems, leaves and other tender plant parts to suck out plant fluids. The site recommends first attempting to control aphids by washing them off with a gentle stream of water. I did this over several mornings and evenings, with my hose set on fine spray, washing both the top and underside of the leaves. After about a week, I still had quite a few aphids, so I sprayed an insecticidal soap, making sure I covered both the top and bottom of leaves. Aphids produce many offspring, so they required an additional treatment.
Scale Insects
Soft scale is a sucking insect, appearing as tiny dots on the leaves or stems of a plant. They can grow up to ¼ inch long and have a smooth, cottony or waxy surface. They feed on the sap of the plant and excrete sticky honeydew, which can attract ants. Mine were brownish-yellow with a waxy color, usually appearing on the underside of the leaves.
I removed badly damaged leaves, checked undersides of the leaves for the scale and scraped off any scale I found using a wet Q-tip. I also checked my other two plants and occasionally found a scale or two on them, scraping them off also. I repotted the infested plant with potting mix. Over time I was able to completely get rid of the soft scale.
Whiteflies
My Buggy Summer Summary
It has been an educational summer learning about these insect pests and dealing with their infestations. I'm gratified I've been able to manage them using less toxic pesticides that are less harmful to beneficial insects and the environment. You can learn more about less toxic pesticides such as insecticidal soaps and oils by visiting the UC IPM website or by watching this video.
Denise is a UCCE Stanislaus County Master Gardener.
[From UC IPM's Pests in the Urban Landscape Blog]
At some point, all of us encounter a pest in our home, garden, or landscape. But you're not alone! UC IPM publishes Pest Notes – a series of more than 150 papers reviewed by experts in the field – to provide science-based information about pests and their management.
These ten Pest Notes were the most frequently viewed online in 2019, with more than 330,000 total pageviews. While it's not a contest, we like to think these are the winners of 2019's most popular pests.
1. Aphids
These small, soft-bodied insects can multiply rapidly, especially in warm weather. Many species exist in California, feeding on vegetables,flowers, fruit trees, and woody ornamentals. Their sticky honeydew encourages growth of sooty mold, while their feeding can distort growth or transmit viruses from plant to plant. Managing ants and supporting natural enemies are two ways you can reduce aphid damage. Learn more about aphids and their manaent in the Pest Notes: Aphids.
2. Thrips
Thrips are tiny, slender insects about the size and shape of a dash printed in a newspaper. Some are beneficial predators that feed on other insects and mites. But most feed on plants, sucking out the cell contents, leaving a discolored speckling on leaves or stunting plant growth. An integrated approach is recommended for management, incorporating good cultural practices, natural enemies, and least-toxic insecticides if needed. For more about thrips monitoring and management, visit our Pest Notes: Thrips.
Peach leaf curl can affect the blossoms, fruit, leaves, and shoots of peach and nectarine trees. The symptoms of the disease first appear in spring, when distorted red foliage emerges. However, focus management for nonresistant varieties in the late fall and early winter, after leaves drop. Read more about this disease in our Pest Notes: Peach Leaf Curl.
4. Scales
Scales are small, legless insects that look like tiny scabs on the stems, leaves, or fruit of plants. While some scale species can weaken a plant when abundant, other species do not appear to damage plants at all. Think you have a problem with these insects? Visit our Pest Notes: Scales for identification and management options.
5. Fungus Gnats
This pest was surprising to find in this year's top 10. Fungus gnats are small flies that often infest soil and potting mixing, emerging from indoor houseplants and becoming a nuisance. The larvae, or immatures, can damage roots and stunt plant growth when present in large numbers. If you do see these flies flitting about, sticky traps may be effective in reducing the problem. However, the presence of gnats and decline of house plants are more commonly due to too much or too little water and improper soil conditions. More information on these frustrating flies can be found in our Pest Notes: Fungus Gnats.
6. Mealybugs
If you've found soft, oval insects that are white in color with wax filaments on your plants, it is likely you have mealybugs. These wingless insects are often found in clustered colonies on indoor and outdoor plants. In yards and gardens, handpicking, pruning, or high-pressure water sprays can reduce populations. For small infestations indoors, spot treatments may help reduce populations. For houseplants with severe infestations, consider disposing of the plant. Find additional information in Pest Notes: Mealybugs.
In residential areas, this not so mysterious marsupial will take up residence under porches, decks, garden sheds, attics, and basements. Opossums are nocturnal omnivores, foraging for fruits, nuts, plants, insects, snails, and even small mammals such as mice. In addition to being a nuisance in residential areas, they carry various diseases that can be transmitted to humans including tuberculosis, spotted fever, and typhus. The best control for opossums is to screen or block access to areas where they may den. You may also choose to hire a professional wildlife control operator to trap and dispense of any opossum visitors. Pest Notes: Opossum has more on the biology and management of these animals.
8. Carpet Beetles
Carpet beetle adults are typically brought into the home on cut flowers or when they fly in through open doors, windows, or holes in screens. The immature beetles feed on animal products such as wool, silk, leather, fur, and hair. Regular cleaning of rugs, upholstered furniture and closets as well as eliminating accumulations of lint, hair, and other debris is an important preventive measure. Check out the Pest Notes: Carpet Beetles for more preventive and management methods of these pests.
9. Ground Squirrels
Ground squirrels are troublesome rodents found throughout most of California. Their network of burrows can be extensive, damaging trees, lawns, and structures. Ground squirrels can also damage many food-bearing and ornamental plants in yards and gardens. For legal management methods, see our Pest Notes: Ground Squirrels.
10. Whiteflies
Whiteflies are not actual flies but are tiny insects that are often found on the underside of leaves, feeding on the phloem of many different plants. Certain species can cause significant loss in vegetable gardens; other species found in fruit trees are less damaging. In home gardens, reflective mulch can repel whiteflies and yellow sticky traps can reduce numbers of high infestations. Additional management information can be found in Pest Notes: Whiteflies.
/span>