Posts Tagged: Peaches
Position Description: Student Assistant III (orchard) The job consists of collecting plant samples and physiological data on fruit trees...
Tom Gradziel Breeding trees takes a long time, says Tom Gradziel, a geneticist at the University of California, Davis. He knows this...
The warmest winter since 1907 in south-central Texas has left its peach crop with inadequate chill hours this year, reported Lynn Brezosky in the San Antonio Express-News.
Without sufficient chill hours over the winter, the buds didn't get the re-boot they need to bloom in proper synchrony, which is important for blossoms to set fruit. The leaves have also been slow to emerge. "The trees look like it's still winter," said Jim Kamas, Texas A&M AgriLife Extenson horticulturalist.
“The lack of chill hours is a big deal,” said Larry Stein, extension horticulturalist with AgriLife Research & Extension Center.
The Texas trouble combined with a cold blast that destroyed half the crop in Georgia and North Carolina this spring mean peaches are likely to be in short supply this year.
The sweet spot, Brezosky wrote, may be California, the No. 1 peach producer in the nation. Roger Duncan, UC Cooperative Extension pomology adviser, could think of no major problems affecting the southern part of the state's fresh market peach crop.
“I think in general it's probably going to be just fine,” he said.
As part of the Farmer-to-Farmer Program sponsored by the Partners of the Americas and funded by the United States Agency for International Development (USAID), retired UC IPM entomologist Walter Bentley and Washington State University entomologist Jay Brunner traveled to Guatemala in April to help growers improve the peach and apple industry. Their primary goal was to identify pest problems and possible solutions to help peach and apple growers improve fruit production, taking into account the region's unique climate.
“The most important issues were horticultural,” said Bentley. “The region's biggest need is for a horticulturist or plant pathologist.”
Some of the peach varieties require 300 to 500 chilling hours.
“Peach trees at elevations of 7,500 to 9,000 feet above sea level bloom for 2 months whereas bloom in California lasts just 10 days," he said. "You would get situations where the top half of the tree was in bloom while the bottom half was already producing fruit.”
This creates an environment favoring disease development and causing further problems for growers if the disease was severe enough to warrant a pesticide treatment. If a tree was partially in bloom while simultaneously producing fruit, it would have to be hand-sprayed multiple times so that the portion of the tree that warranted treatment was sprayed.
Although most of the important issues that Bentley and Brunner found were horticultural or disease-related, there were some insect problems. Many growers had stink bugs and other plant bugs attacking their trees. Spider mites and predatory mites were also observed. Growers sprayed pyrethroids after bloom to help prevent plant bug damage. However, applying pyrethroids reduced predatory mites, leading to an outbreak of spider mites.
After spending seven days touring four to six farms per day and looking at various practices, Bentley and Brunner spent the next week leading workshops for farmers and discussing integrated pest management (IPM) approaches to managing problems. Using the UC IPM website, specifically the Pest Management Guidelines for apples and peaches, Bentley and Brunner were able to teach sampling methods, stress the importance of correct pest identification, and encourage growers to spray with the least toxic and disruptive products. Bentley and Brunner were surprised by the large variety of pesticides available to growers, but were encouraged that farmers were willing to spray only when necessary while being open to other methods of control.
Bentley and Brunner were impressed by the staff that took them around to each farm and by the growers who were receptive to new ways of managing pest problems. The farmers were very appreciative of the advice they received and were very generous. “Everywhere you went people wanted to share what they had,” said Bentley. “They are amazing people.”
Humbled by the experience, Bentley reflected, “I'm glad I went. I've been given a lot in my life and wanted to give back a little.”
Most people deal with ants around their home at some point. Because most ants live outdoors, focus efforts on keeping ants from entering buildings by caulking entryways. Follow good sanitation practices to make your home less attractive to ants. Spraying ants inside the home will not prevent more ants from entering. Use baits to control the ant colony. Pesticide baits work by attracting worker ants who then take the poison back to the nest where the entire colony, including queens, can be killed. In the landscape, ants protect honeydew-producing pest insects from predators, so use sticky barriers or insecticide baits to keep ants out of trees and shrubs.
- Find out more at http://www.ipm.ucanr.edu/QT/antscard.html
Aphids can curl leaves and produce sticky honeydew, but they rarely kill plants and you usually can wash them off with water. When aphid numbers get high, natural enemies such as lady beetles (lady bugs), lacewings, syrphid fly larvae, soldier beetles and others frequently feed on them, eliminating the need for pesticides. Protect these good bugs by avoiding the use of insecticides that can be toxic to a broad variety of insects. Ants protect aphids from these natural enemies, so keep ants away from your garden as well. When pesticides are necessary, use less toxic products such as insecticidal soaps and oils.
- Learn more about controlling aphids here: http://www.ipm.ucanr.edu/QT/aphidscard.html
3. Asian citrus psyllid and Huanglongbing disease
The Asian citrus psyllid (ACP) and the deadly bacterial disease it spreads, Huanglongbing (HLB), threaten citrus trees in backyards and on farms. There is no cure or effective control method for HLB disease. All types of citrus—including oranges, grapefruit, lemons, and mandarins—are affected as well as a few closely related ornamentals. ACP and HLB have already devastated the Florida citrus industry, and now that it is in the Western U.S. it is threatening the California citrus industry as well.
- See where the outbreaks are in California with our helpful Asian citrus psyllid website: http://ucanr.edu/sites/ACP/Distribution_of_ACP_in_California/
- Contact your agricultural commissioner's office, or call the California Department of Food and Agriculture (CDFA) Exotic Pest Hotline at 1-800-491-1899 to confirm a find. Learn more about ACP here: http://www.ipm.ucanr.edu/QT/asiancitruscard.html
Gophers are small burrowing rodents that feed on roots of many types of plants. A single gopher can ruin a garden in a short time, and gopher gnawing can damage irrigation lines and sprinkler systems. In lawns, their mounds are unsightly and interfere with mowing. Early detection is critical to prevent damage. Use both traps and underground fencing to manage gopher problems. Toxic baits are available but can pose threats to wildlife, pets, and children, especially in backyard situations.
- Learn more about protecting your garden and landscape from gophers here: http://www.ipm.ucanr.edu/QT/gopherscard.html
5. Leaf-feeding caterpillars
Caterpillars, which are the larvae of butterflies and moths, damage plants by chewing on leaves, flowers, shoots, and fruit. Caterpillars in fruit or wood can be difficult to manage because they are hidden most of their life and can cause serious damage even when numbers are low. However, many plants, especially perennials, can tolerate substantial leaf damage, so a few leaf-feeding caterpillars often aren't a concern. Handpicking and beneficial predators and parasites often provide sufficient control. Look for feeding holes, excrement, webbed or rolled leaves, caterpillars, eggs, and good bugs.
- Learn more here:http://www.ipm.ucanr.edu/QT/lfcaterpillarscard.html
6. Peach leaf curl
Peach leaf curl is a fungal disease that affects only peach and nectarine trees. Distorted, reddened foliage in the spring is a distinctive symptom. New leaves and shoots thicken and pucker and later may die and fall off. An infection that continues untreated for several years can lead to a tree's decline. To prevent peach leaf curl, treat peach and nectarine trees with a copper fungicide every year after leaves fall. After symptoms appear in the spring, any treatment will not be effective. When planting new trees, consider buying peach tree varieties that are resistant to the disease.
- To learn more about preventing peach leaf curl click here: http://www.ipm.ucanr.edu/QT/peachleafcurlcard.html
Rats eat and contaminate food, garden produce, and fruit, and transmit diseases to humans and pets. Manage rats by removing food and shelter, eliminating entryways into buildings, and trapping. Snap traps are the safest, most effective, and most economical way to trap rats. For Norway rats, place traps close to walls, behind objects, in dark corners, and in places where you have found rat droppings. For roof rats, place traps in off-the-ground locations such as ledges, shelves, branches, fences, pipes, or overhead beams. Ensure traps are out of reach of children and pets.
- Learn more about preventing and controlling rats here: http://www.ipm.ucanr.edu/QT/ratscard.html
Scale insects suck plant juices and are pests of many trees and shrubs. Infestations can cause yellowing or premature dropping of leaves, sticky honeydew, and blackish sooty mold. Plant parts can distort or die back, depending on the species and abundance of scales. Most plants tolerate low to moderate numbers of scales. Provide plants with proper cultural care, especially irrigation. Encourage scale predators such as lady beetles or lacewings and look for parasite emergence holes in scale covers. Use sticky barriers or insecticide baits to selectively control scale-tending ants. Consider replacing problem-prone plants because most scales are highly specific to certain plants.
- Learn more about controlling scale populations here: http://www.ipm.ucanr.edu/QT/scalescard.html
9. Snails and slugs
These slimy mollusks emerge from hiding at night and chew holes in leaves and flowers of many succulent garden plants and fruit. Management requires a vigilant and integrated approach that includes eliminating moisture and hiding spots, trapping, setting up barriers, and handpicking. Regularly remove snails from shelters you can't eliminate such as low ledges on fences, undersides of decks, and meter boxes. Place traps in your garden and dispose of trapped snails and slugs daily. Reduce moist surfaces by switching to drip irrigation or watering in the morning rather than later in the day. Consider snail-proof plants such as impatiens, geraniums, begonias, lantana, nasturtiums, and many plants with stiff leaves and highly scented foliage such as sage, rosemary, and lavender.
- Learn more about controlling snails and slugs with and without pesticides in your garden here: http://www.ipm.ucanr.edu/QT/snailsslugscard.html
10. Weeds in landscapes
Prevent weed invasions in new beds with good site preparation. Keep weeds out with an integrated program that includes competitive plants, mulches, and hand removal. Be particularly vigilant about removing aggressive perennial weeds. You rarely should need herbicides in established landscape plantings. Mulches prevent weed seed germination by blocking sunlight. Remove small weeds by hand before they flower and set seed. Use shallow cultivation or hoeing to remove annual weeds from ornamental plantings. Only use herbicides for special-problem situations before establishing new plantings or for difficult-to-control perennial weeds.
- Learn more about controlling weeds in your landscape here: http://www.ipm.ucanr.edu/QT/landscapeweedscard.html
To see all of the University of California's Statewide Integrated Pest Management Program's information on home, garden, and landscape pests, visit http://www.ipm.ucanr.edu/PMG/menu.homegarden.html
For other short pest “Quick Tips” like the ten above, see http://www.ipm.ucanr.edu/QT/
To read even more in-depth, peer-reviewed information on many other common home and landscape pests in California, see the Pest Notes series at http://www.ipm.ucanr.edu/PMG/PESTNOTES/index.html