What Are Peach Twig Borers: Learn About The Peach Twig Borer Life Cycle

What Are Peach Twig Borers: Learn About The Peach Twig Borer Life Cycle

By: Jackie Carroll

Peach twig borers are the larvae of plain-looking gray moths. They damage new growth by boring into the twigs, and, later in the season, they bore into the fruit. Find out how to manage these destructive pests in this article.

What are Peach Twig Borers?

Don’t confuse the peach twig borer with the peach tree borer. The twig borer bores into tender new growth tips, causing them to wilt and die back. The tree borer bores into the trunk of the tree. Both the peach twig and peach tree borer attack stone fruit such as peaches, nectarines, and plums, and can ruin a crop.

Peach Twig Borer Life Cycle

Peach twig borers have two to five generations every year, depending on the climate where you live. The larvae overwinter under the tree bark, and then make their way to emerging shoots in late winter. They tunnel in and feed until they are mature enough to pupate. Later generations tunnel into the stem end of the fruit.

Crevices in the bark provide hiding places for the larvae to pupate. The adults are plain gray moths that begin laying eggs on the undersides of leaves right away. The generations often overlap so that you can find several life stages in the tree at the same time.

Methods of Peach Twig Borer Control

Peach twig borer control requires careful timing. Here is a list of sprays along with general timing guidelines.

  • Spray horticultural oils before the buds begin to swell.
  • Around bloom time you can spray Bacillus thuringiensis. You’ll need to spray two to three times per generation when you expect a few days of warm weather.
  • Spray with spinosad when the petals fall from the flowers.

Damage from peach twig borers is quite serious on young trees. The insects can kill an entire season of new growth by feeding on the twig tips. Later generations disfigure the fruit and render it inedible.

The good news is that trees generally recover once the insect is gone. Young trees may experience a setback, but there is no reason they can’t produce a crop in future seasons.

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How to Manage Pests

Grape

Branch and Twig Borer

Scientific name: Melalgus (=Polycaon) confertus

Description of the Pest

The branch and twig borer, also known as the grape cane borer, occurs throughout California. Adult borers are dark brown beetles, cylindrical in shape with a pronotum that is wider near the head than the posterior end. Females are about 0.7 inch long adult males are smaller, about 0.3 to 0.4 inch long. Larvae have white bodies that are typically curved in a C-shape and enlarged at the anterior end the head is brown. Branch and twig borers have one generation per year. Adult emergence starts in March and continues through April. Larvae spend up to 10 months in tunnels they excavate.

Damage

Both adults and larvae injure grapevines. Larvae bore into wood at dead or dying parts of vines, often in old pruning scars. Adults burrow into fruiting canes at the base of the bud or shoot, or they burrow into the crotch formed by the shoot and spur. Feeding is often deep enough to completely conceal the adult in the hole. Feeding at the base of shoots on spurs will cause shoots to wilt (flagging) and fall. This pest is most serious in cane-pruned vineyards where feeding on canes can cause them to break when shoots reach a length of 10 to 12 inches, if a strong wind occurs. Shoot wilting can also be caused by Botrytis.

Management

Establishment of branch and twig borer in a vineyard may be attributed to one or two factors: (1) proximity to habitat suitable to the insect, such as riparian or woodland areas, old orchards, or unmaintained vineyards, and (2) failure to destroy or adequately remove dead or damaged parts of vines that may have resulted from disease (such as Eutypa and Pierce's disease) or cultural practices such as T-budding, lowering the vine head, or mechanical pruning.

Chemical control is normally not necessary if good cultural controls are practiced. April treatment of carbaryl for cutworms offers some measurable control of adult borers but may cause mite outbreaks later in the season.

Biological Control

The many species of general predators found under the bark of grapevines may assist in maintaining lower populations. Treatments with commercial formulations of the entomopathogenic nematode Steinernema carpocapsae, which can move through frass tubes to infect larvae, may be of some benefit.

Cultural Control

The best way to manage branch and twig borer in vineyards is to prevent invasion and establishment of the beetles through cultural methods. Wood and brush piles of any kind of tree or shrub should be completely removed from the vineyard or burned before emergence of adult beetles in March. Remove dead or dying portions of vines and destroy them with other prunings. Do not leave grapevine prunings in the vicinity of the vineyard. All prunings must be removed from berms on the vine rows and destroyed to optimize sanitation. If mechanical cane chipping or cutting is used for pruning disposal, the residue should be incorporated into the soil or composted before adult emergence. Good vine health is important for reducing sites of borer establishment in vineyards.

Organically Acceptable Methods

Biological and cultural controls are organically acceptable, including the use of beneficial nematodes.

Monitoring and Treatment Decisions

Look for shoot wilting (flagging) and drying leaves when you monitor your vineyard during the period of rapid shoot growth. In coastal regions, adults continue to emerge through April. Examine the base of these shoots for a 0.4 inch diameter hole. If no holes are present, another possibility is a Botrytis infection. Cut the shoot in half and look for brown discoloration.

After pruning, examine old pruning scars and dead parts of vines for brown frass and fine wood dust filling the holes that were made by borer larvae. Borer holes are detected more easily during the dormant season. No control action thresholds have been established. It is unlikely that borer injury in cordon-pruned vineyards would ever justify chemical treatment if good vineyard pruning and sanitation is practiced. Cane-pruned vineyards with a history of borer injury may require treatment.

IMPORTANT LINKS

PUBLICATION

UC IPM Pest Management Guidelines: Grape
UC ANR Publication 3448

Insects and Mites

L. G. Varela, UC IPM Program and UC Cooperative Extension, Sonoma County
D. R. Haviland, UC IPM Program and UC Cooperative Extension, Kern County
W. J. Bentley, UC IPM Program, Kearney Agricultural Research Center, Parlier
F. G. Zalom, Entomology, UC Davis
L. J. Bettiga, UC Cooperative Extension, Monterey County
R. J. Smith, UC Cooperative Extension, Sonoma County
K. M. Daane, Kearney Agricultural Research Center, Parlier

Acknowledgment for contributions to Insects and Mites:

Statewide IPM Program, Agriculture and Natural Resources, University of California
All contents copyright © 2017 The Regents of the University of California. All rights reserved.

For noncommercial purposes only, any Web site may link directly to this page. FOR ALL OTHER USES or more information, read Legal Notices. Unfortunately, we cannot provide individual solutions to specific pest problems. See our Home page, or in the U.S., contact your local Cooperative Extension office for assistance.

Agriculture and Natural Resources, University of California


Pest & Disease Control for Peach Trees

As it grows, a peach tree may show signs of pests or diseases. Factors such as location, weather, and upkeep play a part in which issues your peach tree encounters, and how well it stands up to them.

Disease-resistant peach trees are easy-care options for growers who prefer a low-spray or no-spray orchard, and — for all peach trees — routine maintenance* can help keep most problems at bay.

*Good maintenance practices include: adequate watering, fertilizing as needed, seasonal pruning, preventive and active spraying, fall cleanup, and winter protection.

NOTE: This is part 7 in a series of 11 articles. For a complete background on how to grow peach trees , we recommend starting from the beginning.

The following are merely intended as a means of identifying potential issues. Don’t be alarmed — a peach tree may experience a few of these in its lifetime, but certainly not all at once.

Peach Tree Pests

Aphids

Tiny, pinhead-sized insects, varying in color depending on the type. Will cluster on stems and under leaves, sucking plant juices.

Symptoms: Leaves curl, thicken, yellow, and die. Aphids produce large amounts of a sticky residue called “honeydew” that attracts insects like ants. Honeydew also becomes a growth medium for sooty mold.

  • GardenTech® Sevin® Concentrate Bug Killer
  • Bonide® Fruit Tree Spray

  • Bonide® All Seasons® Horticultural & Dormant Spray Oil
  • Bonide® Insecticidal Soap
  • Bonide® Citrus, Fruit & Nut Orchard Spray
  • Bonide® Neem Oil
  • Monterey Fruit Tree Spray Plus
  • Monterey Horticultural Oil

Lygus Bugs and Stink Bugs

Lygus bugs are small oval insects that are brown, green, gray, or almost black with a yellow “V” on the back. Stink bugs are usually gray or brown, shield-shaped and about ½-inch long.

Symptoms: Lygus bugs damage fruit and blossoms. Stink bugs puncture fruit and suck out the juice, causing sunken spots on young fruit or deformed mature fruit (cat-facing). Both can be headed off by planting your peach trees away from hay fields, which serve as a host.

  • Bonide® Captain Jack’s™ Deadbug Brew Garden Dust
  • Bonide® Borer-Miner Killer
  • Bonide® Insecticidal Soap

Oriental Fruit Moth

Pests and damage are similar to the Codling Moth. Adults are small, ½-inch grayish moths. Larvae are pinkish-white with a red-brown head, about ½-inch long. Pheromone traps are an option for luring moths.

Symptoms: Damage first appears on vegetative growth, and left untreated will eventually infest fruit. Larvae tunnel in through the stem and often exit near the pit.

  • Bonide® Fruit Tree Spray

  • Bonide® All Seasons® Horticultural & Dormant Spray Oil
  • Bonide® Insecticidal Soap
  • Bonide® Captain Jack’s™ Deadbug Brew Garden Dust

Borers

Includes: American plum borer, Pacific flatheaded borer, Peach twig borer, Peachtree borer, Shot hole borer

These pests burrow and feed underneath the bark on the sapwood, weakening the tree and leading to death. Borers may target the graft location (in young peach trees) for laying eggs as well as damaged or sunken areas, and even a few inches below the soil line. Grubs have cream-colored bodies. Difficult to control once infested preventive action is the best defense.

Symptoms: A thick, gummy substance (sap) leaking from round holes on the trunk or in a crotch of the tree. Grubs tunnel through trunks, weakening and eventually killing the tree. Eggs hatch and larvae tunnel into tree’s vascular tissue.

  • If infested, use a fine wire to try to pierce, mash, or dig grubs out.
  • Traps (tanglefoot-coated logs or posts) can lure adults. Remove from site and burn after trapping.
  • Preventive spraying (including the ground around the roots)

  • GardenTech® Sevin® Concentrate Bug Killer

  • Contact local county Cooperative Extension for further advice

Fall Webworm

This species is similar to the eastern tent caterpillar, but constructs its web over the end of the branch, rather than in tree crotches. It feeds on nearly all trees, excepting conifers. The webworm caterpillar is about an inch long with a black to reddish head and light yellow to greenish body with a mottled stripe of two rows of black tubercles and tufts of long whitish hairs. Adults appear as white moths with dark spots on the wings.

Symptoms: Branch ends are encased in a large web where larvae feed, skeletonizing the leaves.

  • Remove webs with a rake (caterpillars are removed with webs) and burn

  • Bonide® Fruit Tree Spray

  • Bonide® All Seasons® Horticultural & Dormant Spray Oil
  • Bonide® Insecticidal Soap
  • Bonide® Thuricide® BT

Leafroller

Small caterpillars, about an inch long in colors from pale yellow or green to brown. Leafrollers often have dark heads.

Symptoms: Leaves and blossoms are rolled and webbed together where larvae feed. Foliage eventually becomes skeletonized. Leafrollers do not burrow into fruit, but may scar it.

Hand-removal of webbed foliage and keeping area free of weeds and debris may be enough to manage the pest.

  • GardenTech® Sevin® Concentrate Bug Killer
  • Bonide® Fruit Tree Spray

  • Bonide® All Seasons® Horticultural & Dormant Spray Oil
  • Bonide® Captain Jack’s™ Deadbug Brew Garden Dust
  • Bonide® Thuricide® BT
  • Bonide® Citrus, Fruit & Nut Orchard Spray
  • Bonide® Neem Oil
  • Monterey Fruit Tree Spray Plus
  • Monterey Horticultural Oil

Nematodes

Includes: Root-knot nematodes, Ring nematodes, Lesion nematodes, Dagger nematodes

Nematodes (microscopic worms) live in the soil and in plant tissue, and can do a lot of damage to peach trees. Have the soil tested by your county extension agent prior to planting to determine the extent of their presence.

Symptoms: Nematodes perforate tissue cells and feed on them, usually damaging the roots. Tree growth is stunted and leaves may show signs of yellowing (chlorosis). Sandy soils are more susceptible.

Fumigate pre-planting (in the fall, while the temperature is still about 55 degrees), or alternate nematode-unfriendly cover crops. Purchasing peach trees with nematode-resistant rootstock is the best prevention.

  • Nimitz, a nematicide approved by the EPA in 2014, is a non-restricted use pesticide with less stringent regulatory restrictions and reporting guidelines than fumigators. As of mid-2016, it was not yet widely available in retail gardening stores.

Plum Curculio

Adult is brownish gray, 1/5-inch long, hard-shelled beetle with a long snout and 4 humps on its back.

Symptoms: Cuts a crescent-shaped hole in fruit skins and lays eggs inside. Grubs hatch and tunnel within fruit. Fruit may drop prematurely or have grubs/worms or tunnels inside at harvest.

  • Site Cleanup.
  • Thin crescent-shape scarred fruit as soon as it appears.
  • Remove dropped fruit as soon as it appears to avoid re-infestation.

Scale

Includes: San Jose Scale and other types of scale

Usually on bark of young twigs, branches. Gray, circular bumps protect the female, whose eggs hatch immediately into small yellow crawling insects. The young scale secrete a white wax, which eventually turns black. Scale may also be on the fruit.

Symptoms: Sap-feeding weakens the tree.

  • GardenTech® Sevin® Concentrate Bug Killer
  • Bonide® Fruit Tree Spray

  • Bonide® All Seasons® Horticultural & Dormant Spray Oil
  • Bonide® Insecticidal Soap
  • Bonide® Citrus, Fruit & Nut Orchard Spray
  • Bonide® Neem Oil

Tarnished Plant Bug

Yellowish-brown, winged insect that may have black spots or red stripes.

Symptoms: Damage is caused by injecting toxins into buds and shoots, causing stunted vegetative growth and sunken areas (often called “cat-facing”) on fruit.

  • Bonide® Insecticidal Soap
  • Bonide® Citrus, Fruit & Nut Orchard Spray

Tent Caterpillar

Adults are moths. Caterpillars are a hairy, grayish brown with cream-colored spots or stripes down the back.

Symptoms: Encases large areas in webbing and feeds on enclosed leaves.

  • Remove webs with a rake (caterpillars are removed with webs) and burn.

  • Bonide® Fruit Tree Spray

  • Bonide® Insecticidal Soap
  • Bonide® Thuricide® BT

Thrips

Tiny, slender, fringed-wing insects ranging from 1/25-inch to 1/8-inch long. Nymphs are pale yellow and highly active. Adults are usually black or yellow-brown, but may have red, black, or white markings.

Symptoms: Feeding occurs on vegetation by puncturing and sucking up the contents, causing appearance to be deformed or discolored (similar to damage by mites and lace bugs).

  • Bonide® Citrus, Fruit & Nut Orchard Spray
  • Bonide® Insecticidal Soap
  • Monterey Fruit Tree Spray Plus
  • Monterey Horticultural Oil

Peach Tree Diseases

Anthracnose

Also “bitter rot” of peaches

Anthracnose is an infection that affects many species of fruit trees, including peach. Most of the damage is cosmetic, but still needs to be controlled. Rain and irrigation systems can spread the disease, which tends to occur in warm, wet weather.

Symptoms: Anthracnose of peach trees usually occurs on ripe or nearly ripe fruit. Small brown or tan lesions, which enlarge and darken, gradually become circular and slightly indented. In early stages, these lesions may be confused with those of brown, black or white rot, but anthracnose spots are firmer and bigger, and are often accompanied by rings of pink spore masses. Leaves and twigs remain unaffected. Anthracnose will not kill the tree, but will damage the fruit/yield.

Bonide® Captan Fruit & Ornamental (wettable powder)

  • Bonide® Copper Fungicide
  • Bonide® Neem Oil
  • Monterey Fruit Tree Spray Plus

Armillaria Root Rot

Also “oak root fungus”, “shoestring rot”, and "mushroom rot"

All stone-fruit rootstocks are susceptible to Armillaria root rot, which smells distinctly like mushrooms and occurs on the upper roots and/or crown of the tree. This destructive fungus lives within dead and living roots is transferred from root system to root system. It can live for up to 30 years.

Symptoms: Roots infected with Armillaria mellea have whitish-yellow fan-shaped mats between the bark and the wood. The tree trunk is girdled. Dull, yellowed, or wilted foliage is usually the first sign of trouble infected trees usually die slowly.

Exposing an infected crown and upper root area of a peach tree may help to slow its growth into the crown. In spring, remove soil from around the base of the tree to a depth of 9 to 12 inches. Leave the trunk exposed for the remainder of the growing season. During the spring, summer, and fall, keep the upper roots and crown area as dry as possible. Recheck the hole every few years to make sure it has not filled in with leaves, soil, and other matter the hole must be kept open and the crown and upper roots exposed.

Brown Rot

Brown rot is a fungal disease that commonly affects stone-fruit trees, including peach trees, especially after a long, warm, wet spring. It is one of the most common peach-tree diseases. It affects the fruit tree’s flowers and fruit crop, but is not fatal. Fortunately, brown rot is easy to spot, prevent, and treat.

Symptoms: Blossoms may brown or wilt. Dark sunken spots appear on new shoots, and leaves on infected limbs will be brown and droopy. Affected fruit develops small spots of rot that enlarge quickly, developing fuzzy tan/grey spores that cover the fruit surface. If left on the tree, fruit shrivels, darkens, and hardens into “mummies.”

Plant a resistant variety, like Venture in a well-drained location. Prune regularly to keep trees open to light and air circulation, and remove any pruning debris, damaged or diseased fruit and limbs, as well as fallen fruit to avoid sites for fungi to thrive (do not compost). Thin fruit to avoid good fruit touching infected fruit. Disinfect your pruners between cuts to avoid spreading the fungi.

  • Bonide® Copper Fungicide
  • Bonide® Captan Fruit & Ornamental
  • Bonide® Fung-onil™ Multi-Purpose Fungicide

Spray preventatively if brown rot is problematic in your area, even before symptoms appear.

Canker (bacterial and cytospora)

Cytospora canker is caused by the fungus Cytospora spp. and attacks trees via weak or injured bark. Bacterial canker is caused by Pseudomonas syringae. Both tend to occur during cool, wet weather. They act and are treated similarly.

Symptoms: Infection appears as yellow-orange and black regions that later ooze a gummy substance which may have a foul odor. Cankers eventually develop in the branches, encompassing the circumference of the wood until it dies.

Prune off infected twigs and limbs where cankers have affected the branch. Cut out cankers that are less than half the branch circumference. Use a small, sharp knife and score the wood all the way around the canker, about an inch away from it. Dig the tip of the knife into the wood and bark as you work, and maintain a 1-inch margin around the circumference of the canker.

Slip the knife under the bark and remove the diseased inner bark, which is usually a rusty brown color. Round the edges of each incision to promote rapid healing, but do not remove the wood from the uninfected area below the canker.

Clean up any wood chips or debris and either burn it or dispose of it in the trash. Do not compost infected debris. Bleach the knife used to excise the canker, rinse and pat dry.

Apply fungicide spray to small wounds during wet periods and during dormant periods.

Bonide® Captan Fruit & Ornamental (wettable powder)

  • Bonide® Copper Fungicide

Crown Gall

Caused by Agrobacterium tumefaciens — a bacterium that inhabits the soil and causes rapid, abnormal growth (developing into galls). Can spread through injury to roots in the soil as well as through gardening tools carrying the bacterium.

Symptoms: Trees appear stunted and slow growing leaves may be reduced in size. In mature, fruit-bearing aged trees, may see little or no fruit. Woody, tumor-like growths called galls appear, especially at the crown (ground level) and below. Growths can restrict water and nutrient flow, but often the damage isn’t extensive enough to cause immediate or total death. If tree has died, inspect roots for hard, woody ‘tumors’ to identify Crown Gall as the cause. Note: Crown Gall is not the only thing that can cause stunted trees.

  • Purchase gall-free nursery stock. Crown gall symptoms are generally well developed on finished nursery stock, making inspection a useful prevention strategy.

  • Contact local county Cooperative Extension agent for further advice

Peach Leaf Curl

This is a common fungal disease that affects peaches and nectarines. Leaf curl can severely inhibit fruit production. Disease fungi overwinter underneath the bark, around buds and in other protected areas. During cool, wet spring weather, the spores infect new leaves as they emerge from the buds. Later, the fungus produces millions of new spores, which are splashed or blown from tree to tree.

Symptoms: Leaf curl shows up in the spring as reddish areas on new leaves, which then thicken and crinkle, causing them to “curl.” Spray the whole tree after most all of leaves have dropped in the fall, and again in the early spring, just before buds open.

  • Select resistant varieties whenever possible.
  • Keep the ground free of leaves and debris, especially over the winter.
  • Prune and destroy infected plant parts as soon as you see them.

  • Bonide® Copper Fungicide Spray or Dust
  • Bonide® Citrus, Fruit & Nut Orchard Spray
  • Monterey Fruit Tree Spray Plus
  • Monterey Horticultural Oil

Phytophthora Root Rot and Crown Rot

Soil pathogens in the genus Phytophthora can cause crown and root rot diseases of almost all fruit and nut trees, as well as most ornamental trees and shrubs. This disease appears if the soil around the base of the tree remains wet for prolonged periods, or when the tree is planted too deeply.

Symptoms: Infected trees often wilt and die quick as soon as the weather warms up. Leaves may turn dull green, yellow, or even red or purplish. Symptoms may develop first on one branch then spread to the rest of the tree. Dark areas appear in the bark around the crown and upper roots. Gummy sap may ooze from the diseased trunk. Reddish-brown areas may show between the bark and wood.

Good water management/drainage is the key to prevention. Never cover the graft union with soil and try to avoid direct watering of the crown. If you suspect crown rot, carefully cut away affected bark at the soil line. Trees can sometimes be saved by removing soil from the base of the tree down to the upper roots and allowing the crown tissue to dry out.

  • Bonide® Captan Fruit & Ornamental
  • Bonide® Fung-onil™ Multi-Purpose Fungicide

  • Bonide® Copper Fungicide

Powdery Mildew

Caused by Podosphaera leucotricha — a fungus that overwinters in buds and emerges during humid, warm weather progressively throughout the growing season.

Symptoms: Whitish-gray powdery mold or felt-like patches on buds, young leaves, and twigs. Leaves may crinkle and curl upward. New shoots are stunted.

  • Bonide® Copper Fungicide Spray or Dust
  • Bonide® Citrus, Fruit & Nut Orchard Spray
  • Monterey Fruit Tree Spray Plus
  • Monterey Horticultural Oil

“Tranzschelia discolor”, commonly referred to as rust, overwinters in twigs or in leaves on the tree. A preventive fungicidal regimen is recommended: apply fungicide one, two and three months before harvest in areas prone to early-season outbreaks of the disease, and post-harvest in areas where disease is less of a problem, or emerges late-season.

Symptoms: Rust causes cankers to form on branches, followed by the appearance of pale yellow-green spots on both upper and lower leaf surfaces. The spots have an angular shape and eventually turn bright yellow. Spots on leaf undersides develop brown/orange spores. In some areas, rust damage extends to the fruit.

  • Bonide® Captan Fruit & Ornamental
  • Bonide® Fung-onil™ Multi-Purpose Fungicide

  • Bonide® Copper Fungicide

Caused by Venturia inaequalis — a fungus that overwinters in fallen leaves and pruning debris. Favors cool, wet weather (typically in spring).

Symptoms: Spots on young leaves are velvety and olive green, then turn black leaves wither, curl and drop. Fruit also has spots, is deformed, knotty, cracked and drops.

  • Plant scab-resistant peach trees if possible, especially in areas where peach scab is a known issue
  • Remove and dispose of pruning debris. Fall clean-up is essential to controlling overwintering fungus.

  • Bonide® Fruit Tree Spray
  • Bonide® Captan Fruit & Ornamental

  • Bonide® Citrus, Fruit & Nut Orchard Spray

  • Contact local county Cooperative Extension for further advice (including recommended scab-resistant varieties that are known to perform well in the area)

Shot Hole Blight (coryneum blight)

This disease gets the name from infections that appear as small tan spots on young leaves. The spots turn brown with purple borders, and the spotted areas eventually drop out of the leaf, appearing as if they were hit with a BB gun or buckshot.

Symptoms: Small, red-brown or purplish spots occur on new leaves and shoots. The spots expand, and the center turns brown. Tiny, dark specks sometimes form in the center of lesions, especially on leaves. Spots on young leaves have a narrow, light green or yellow margin and their centers often fall out as leaves expand, leaving “shot holes.”

Peach tree buds are killed in the winter. Fruit may become rough, with spotting on the surface. Circular lesions may develop on branches.
Some varieties may be less susceptible, so choose carefully. Where disease incidence is high, fungicides may be applied. On peach trees, a dormant spray of copper fungicide in late fall will work well.

  • Keep the ground free of leaves and debris, especially over the winter.
  • Prune and destroy infected plant parts as soon as you see them.
  • Avoid overhead sprinklers to keep foliage drier.

  • Bonide® Copper Fungicide Spray or Dust
  • Monterey Horticultural Oil

Other Peach Tree Issues

No Blossoms or Fruit

Peach trees take about 2 to 4 years after planting (on average) before they bloom or bear fruit. If enough time has been allowed to pass, and the peach tree is otherwise healthy, there are a few things to do to help it become fruitful.

  • Make sure a pollinator variety is present. Most peach trees are self-fruitful and do not require another different variety of peach tree to bear fruit, but be sure to check that this applies to the variety you are growing. If a pollinator is required, choose another compatible peach variety.
  • Make sure your peach tree variety is recommended for your zone. Low winter temperatures can injure sensitive fruit buds, hindering fruit production.
  • Space trees far enough apart to help avoid nutrient or light competition. Adequate space encourages a healthy and productive tree. Spacing can be estimated by the mature spread of the tree.
  • Prune to help keep the fruiting wood and vegetative wood in balance so that there isn’t too much leaf development in lieu of blossom development in mature trees — or too much fruit-bud development and not enough leaves to “feed” the fruit.
  • Know your soil. Soil conditions, and the presence of necessary nutrients, help keep a peach tree’s roots supplying nutrients through its vascular system. If the soil is poor, or poorly drained, this affects the health and viability of the tree as a whole. If the tree is being over-fertilized, especially with a fertilizer high in nitrogen, it may develop lush, vegetative growth (leaves and branches) instead of developing fruit buds or blooming.

Sunscald and Sunburn (Scorching)

Sunscald/sunburn occurs during hot, dry growing seasons — with or without humidity in the air, but most commonly when humidity is low. Sunscald is also called winter injury or “southwest injury” as it commonly affects the southwest side of tree trunks during winter. Brown, crispy edges appear on leaves. Warm, clear days cause bark to expand and nights that are several degrees cooler will cause the bark to contract, damaging cells and causing splits and cracks in the trunk.

  • Protect trunks prior to winter with tree guards or a diluted solution of water and white latex paint (50/50).
  • Water new trees every 7 to 10 days during the growing season (if there is no rain within the week), or as needed (as the soil becomes dry to the touch).
  • During the growing season, consider constructing a temporary shade cloth to protect trees from the sun on hot, dry days. Water as needed (see above).

Water Stress

Can be caused by both overwatering and underwatering. Overwatering commonly presents as pale green to yellow leaves and leaf drop, which can weaken a tree, lead to root rot, and ultimately kill the tree. Underwatering often presents as discolored (usually yellowed), dry leaves. Tree may appear to wilt overall. Prolonged lack of water can kill the tree.

  • Water new trees every 7 to 10 days during the growing season (if there is no rain within the week) or as needed (as the soil becomes dry to the touch).
  • If planted in a location where the soil does not adequately drain water after heavy rains (leading to standing water), relocate the tree as soon as possible.
  • If drought-like conditions persist, consider slow-trickle drip irrigation to allow water to reach the roots rather than wash over soil surface.

Wind Injury

Symptoms: Can involve injury such as leaning/uprooted trees, breaks, tears, or wind-burned foliage. Depending on the severity of the injury, a peach tree can either bounce back from minor damage or succumb to the wind-caused harm. This is determined on an individual basis and the health of the tree before the damage occurred.

  • Adequately tamp soil around the tree’s roots (and thoroughly water) at planting time to remove air pockets and ensure good contact with the soil. Air pockets and loose soil around the roots can cause the tree to rock easily, leaving it vulnerable to leaning or uprooting.
  • Use tree stakes for new trees, dwarf trees, and trees planted in high-wind areas to help support upright growth and avoid leaning, uprooting, and breaking.
  • Selectively thin fruit that may be weighing down limbs to reduce stress from the weight, and avoid tears or breaks during gusty weather. Be aware: pests and disease may also take advantage of resulting broken or torn areas if damage occurs.

If tender new foliage is blown or whipped around by the wind, it may appear discolored (dark — like a burn or bruise). Damaged leaves can be removed to encourage healthy, new growth.


Disease and Insect Control for Homegrown Peaches and Plums

It takes a committed gardener to consistently produce high-quality peaches or plums. These fruit crops are especially demanding when it comes to pest management because peaches and plums are attacked by many insects and diseases that must be controlled to have a successful crop. This publication provides information on how to identify pests and when to treat. It also includes a recommended spray schedule for disease and insect treatments based on stage of crop development.

This publication has been developed specifically for small-scale home orchards. The insecticide and fungicide recommendations given here are based on non-restricted use products that are readily available from local lawn and garden centers and sold in container sizes appropriate for small orchards. Commercial producers and large-scale hobby orchardists who have a private pesticide applicator license should obtain a copy of the Southeastern Peach, Nectarine, and Plum Pest Management and Culture Guide and follow the recommendations for pest management in commercial orchards.

Peach brown rot. The “fuzzies” on the left side of the peach are the spores produced by the fungal disease. Notice the light brown discolored area between the “fuzzies” and the bright color of the peach. This is the leading edge of infection where the fungus is invading and consuming the fruit spores will soon appear on the outside.

Diseases of Peaches and Plums

Some of the diseases that attack peaches in Mississippi are very aggressive, and missing one or two key sprays can result in the loss of most of a peach crop, especially if sprays are missed when weather conditions are favorable for disease development. Fungicides protect the plant or fruit from infection they do not eliminate the infection once it has occurred. While fungicide sprays are necessary to grow peaches in the Deep South, much of the real protection from these diseases will come from removing and destroying the inoculum (or “seed”-producing structures) of these diseases.

The following disease descriptions may seem extensive to the point of “too much,” but they will help you identify these disease infections so that you can prune and remove these structures from your trees, reducing the disease pressure. Similarly, descriptions of weather conditions necessary for a disease may seem unnecessary, but knowing the conditions that encourage the disease can help you decide how important it might be to get out and spray before or between rains.

When tree parts suspected of harboring disease are removed or pruned from the tree or surrounding soil, immediately place them in a plastic bag. Tightly close the bag and destroy it. If the limbs are too large to fit in the bag, place them well away from and downwind of the trees. Burn or otherwise remove them as soon as possible. Do not allow them to accumulate.

The peaches here have been infected with brown rot and have fallen to the orchard floor. They will continue to produce spores and infect other peaches. They may mummify and, especially if partially buried, produce some small mushrooms that produce a second kind of spore that will infect spring blossoms.

Brown Rot

Brown rot is a serious peach disease, but it is not very common on plums in Mississippi. The disease attacks many plant parts (blossoms, twigs, shoots, and fruit) from spring through harvest. Fungicides will help suppress the disease but control it only moderately when conditions favor the disease, especially in late season near harvest. Nonetheless, fungicides are almost a necessity in our climate.

The fungus that causes brown rot (Monilinia fruticola) overwinters in twig cankers, fruit mummies, and peduncles (stem-like structures that attach the flower/fruit to the branch). Removing these overwintering sites after harvest will reduce disease pressure the next season.

The brown rot fungus becomes active in early spring, about the time the flower buds develop into the “pink” stage. Warm, humid, wet weather favors rapid spread and disease development. The optimal temperature for disease development is 75°F, but slower disease development can occur as cool as 39°F and as warm as 86°F. Storms are a perfect time for spore movement because the free water (rain, dew, irrigation) on the trees provides the moisture for these seeds (spores) to germinate and infect the plant. The free water will need to be present for longer periods the further the temperature is from the 75°F optimum.

As the fungus grows, it produces spores, or seed-like structures. They are very small (like very small pollen) and easily carried by wind and rain. The fruiting areas that produce the spores are small, ash-gray tufts that emerge from the surface of the brown-colored infected tissue. Infections in mature fruits show these spores clearly.

Twig cankers are dead (brownish), sunken areas. The canker may stay on one side of the twig or may girdle (encircle) it. A weak or dead twig or fruit spur will emerge from the canker. Some cankers may be small and difficult to find. Larger infected twigs or spurs may ooze sap, which looks like a bubble of dark brown viscous gum. This is called gummosis. The amount of gummosis varies from none to a fair amount and will only occur on larger twigs and branches.

Mummified fruit is a favored location for many diseases to overwinter. The “mummies” are fruit that have dried, leaving an unappetizing mock fruit. They might be hanging from the tree, lying on the ground, or, worse, partially buried in the soil near the tree. Infected fruit mummies that have been buried or partially buried in the soil may produce small, brown, cup-shaped mushrooms (apothecial stage of the fungus). The mushrooms produce a different kind of spore that infects the trees. Retrieving and destroying all mummies will be very beneficial.

The fungal spores commonly infect the flower, fruit, peduncle, and twigs. The peduncle is the stout stem that connects the flower/fruit to the tree branches. Early-season infection of the twig and blossoms creates the small cankers from which the fungus produces more spores. These early-season infections can substantially influence fruit infections later in the season.

In Mississippi, attacks on the flower by brown rot disease are not common. When they do occur, it seems to foretell a very challenging season for the grower, because the disease becomes prevalent. Symptoms of flower infection are called blossom blight. The blossoms will brown and probably collapse. The blight appears 3–6 days after infection, which will probably have occurred during a rain, irrigation, or long, heavy dew event.

Symptoms of shoot and twig infection will occur 3–4 weeks after infection. They may or may not follow from infected blossoms, from which the fungus travels down the peduncle into the twig or branch. As these infections progress, whole clusters of blossoms or leafy branches may wilt and die. This is because the canker cuts off the flow of water to these parts of the tree. Prune these out by cutting into healthy wood below the lesion as soon as possible. Remember to place the cut parts in a plastic bag, and seal and destroy it.

Brown rot may attack fruits at any time, but older fruit are more susceptible. Infection may occur directly through the skin of the fruit, through natural openings, and through wounds, especially those made by insects.

Direct your spraying and sanitation controls toward the sources of infection. Remove old, mummified fruit, peduncles, and infected twigs/branch parts from the tree and ground before spring. If harvest weather favors the disease, regular and thorough sprays will be necessary if you want to save your fruit from destruction by brown rot. Fungicides work preventively—they cannot eradicate an infection. This means you must be proactive and keep these protective sprays on the targets the fungus most likes to infect.

Peach Scab

Scab is a fungal disease caused by Cladosporium carpophilum. Although the primary damage caused by this disease is visual, it can provide entry wounds for brown rot. Heavy infections may also cause the peach to split.

The disease symptoms are velvety, olive-green spots on the fruit, leaves, or twigs. The spots are about one-sixteenth of an inch and enlarge to one-eighth of an inch. You will begin seeing these spots about 3 weeks after petals fall. When the spots are on the fruit, they will usually be on the stem-end side. When infections are numerous, they may merge and may cause the fruit to split. The fruit spots are confined to the skin they do not enter the flesh.

Like brown rot, peach scab overwinters in twig lesions. Infections of twigs occur on new growth and are difficult to see. They start as raised, oval to circular areas that are pretty much the same color as the surrounding tissue. As they age, they may turn brownish. By season’s end, the lesion edges may be somewhat purple and the lesions may have grown to one-fourth to one-half of an inch. The second season of infection is when these lesions will produce most of the spores. The spores are both air- and water-borne and require 24 hours of high relative humidity to germinate.

Peach Leaf Curl

Peach leaf curl disease is caused by the fungus Taphrina deformans. Peach leaf curl does not occur regularly on most peach and plum trees, but it can be a serious disease. Standard fungicide sprays used to control other diseases, such as brown rot, normally control this disease.

The disease is favored by moderate temperatures (48–81°F optimal temperature for development is 68°F) and wet weather during early bud development. The humidity needs to be above 98 percent.

Two stages of the fungus make this disease unique. One type of spore is produced from curled (infected) leaves in the spring. The fungus can infect either side of the leaf. Infected leaf symptoms include yellow to reddish areas that get thicker as the fungus grows. The infected and thickening portion of the growing leaf causes that part of the leaf to grow more slowly than the rest of the leaf, causing the leaf to curl. These thick areas produce spores that, when germinated, produce a different phase of the fungus that grows on and along with the shoot tips, keeping up with their growth.

Sanitation and cultural controls are not effective for this disease. Some peach cultivars have been bred for resistance to this disease, so resistant cultivars and fungicides are the primary management tools.

Copper sprays during tree dormancy, as well as in-season applications, are important. Once established in a group of trees, even radical pruning to remove infections will have only modest success controlling the disease.

Shot Hole

Shot hole is a fungus disease (Wilsonomyces carpophilus) that gets its name from the leaf symptoms—smallish brown spots that fall out, leaving a “shot” pattern in the leaf. The disease is present in Mississippi.

This fungus starts to cause problems during wet winter months when buds and twigs infected the previous season produce spores. The fungus infects and kills dormant buds. Some buds may have a varnished appearance, which results when tree gum seals the infection from the rest of the plant.

Stem lesions range from about one-tenth to three-eighths of an inch in diameter. Leaf and fruit lesions start as small, purplish areas that expand and turn brown. All may have a velvety, brownish mass of fungus in the middle during moist and humid weather. When the weather turns warm, the leaf lesions will fall from the leaf, leaving the “shot hole” appearance. Fruit lesions will be on the upper (stem) side and will become rough-textured, almost corky.

To manage this disease, you must protect the dormant buds. A single application of fixed copper or Bordeaux mixture before fall/winter rains provides winter-long protection. Growing shoots and fruits also need protection. A spray application immediately after fruit set is most common. Usually Captan is used because copper fungicides used at this time of year can cause plant injury (phytotoxicity). No resistant cultivars are available.

Bacterial Spot

As the name indicates, this disease is caused by a bacteria (Xanthomonas arboricola pv. pruni). It can be very aggressive in the eastern United States because of generally higher humidity, wetter conditions, and longer dew periods than in the western states. Very susceptible cultivars cannot be grown here at all.

The bacteria depend upon free moisture (dew, rain, irrigation) to reproduce and for lesion growth. Rain driven by wind spreads the bacteria through the tree and among trees. Infections will be worse on the sides of the trees facing the winds that brought the infection. The optimal growth temperature is 75–84°F. The disease affects twigs, shoots, leaves, and fruits.

Leaf symptoms start as a water-soaked dark green spot that expands until it meets the veins inside the leaf. Because the leaf veins keep the lesion from spreading for a while, angular lesions (lesions with sharp corners) about one-sixteenth to one-eighth of an inch are a key that bacterial spot is the problem. If warm, wet weather continues, the lesions may enlarge and merge. As the lesions age, the insides will turn from a water-soaked dark green to a light purple color. As the weather dries, the lesions may turn brown and fall from the leaf. The lesions will be more common in areas of the tissue where water sits for any period of time, such as along the leaf midrib, on leaf tips, or along lower areas of the leaf margins. Leaves with numerous lesions may turn chlorotic (yellow) and fall from the tree. This bacterial pathogen usually enters twigs through leaf scars, which are places where a leaf has fallen from the twig. Lesions that develop on the previous year’s growth are called “spring cankers” or “black tip.” They were infected by the bacteria moving through the leaf scars the previous autumn. Spring cankers appear as slightly raised blisters. They can expand to as long as an inch along the twig. Black tip is confined to the terminal bud area of the twig. The bud fails to open, and a dark canker can extend up to 1 inch down the twig from the bud.

Summer cankers form on newly growing shoots and are seen in late spring or very early summer. Favorable weather conditions may cause rapid bacterial growth, and the infection may kill the shoot.

Fruit symptoms first become apparent several weeks after petal fall. They appear as small, water-soaked, brownish lesions that might be mistaken for insect damage. As infection progresses, gum may ooze from the lesions during periods of high humidity. As the fruit and the infection age, the lesions may crack open and perhaps sink.

Bacterial infections can only be managed with proper sanitation, copper-based products, or antibiotic sprays and host plant resistance. There are cultivars with resistance to this disease. Common resistant cultivars include Redskin, Redhaven, Loring, Candor, Biscoe, Dixired, Sunhaven, Jefferson, Madison, Salem, Contender, Harrow Beauty, and Harrow Diamond. Bacterial spot is a very difficult disease to manage. If you are planting peaches or plums, please select a resistant cultivar.

Black-knot

Black-knot is caused by the fungus Apiosporina morbosa. The primary symptom in established infections occurs on wood and consists of outgrowths or knots on shoots, spurs, branches, and trunks. Old knots are hard, dark, almost black, raised areas. The raised areas are often invaded by insects whose damage may, in turn, be invaded by secondary pink or white fungi.

Infection starts in the spring when the tree enters the green tip stage, with most infection occurring between very early bloom and the end of petal fall. Spores released from 2-year-old infected tissue are moved by wind and splashing rain to new shoot growth. For the spores to be made, at least 6 hours of rain are needed at 70°F, which is close to the optimal growth temperature for the fungus.

Symptoms of new shoot infection are difficult to detect. Perhaps the most obvious symptoms are the branches growing at right angles. Less obvious are the small, olive-green knots that might be firm to somewhat corky. The knots later turn hard and will probably break off easily.

Black-knot can be a problem in Mississippi plum trees, usually when those trees are within about 600 feet of wild plums and cherries or when the trees have not received care for a substantial length of time. Fungicides apparently suppress the disease, but pruning out black-knot cankers anywhere on the tree is a necessity. Wild plums and cherries within 600 feet should be removed if possible. Prune infections in wood about 4 inches below the lowest symptom of infection. Midsummer pruning is the most effective since the outer swelling is the closest to the infection on the inside of the wood. Fungicides should be applied during the time of active shoot growth if the disease is a problem in your area.

Plum Pockets

The fungus Taphrina causes plum pockets disease, but, while present in Mississippi, it has not been a serious problem. It is included here because it occurs frequently enough for many people who raise plums to see it. Although the fungus infects leaves, shoots, and fruit, symptoms are most obvious on fruits. Symptoms become obvious on all plant parts 6–8 weeks after bud break.

Fruit become enlarged (up to 10 times their normal size), wrinkled, and distorted. The centers of the fruit are spongy or hollow and may or may not contain a pit. When the fruits dry, they turn brown to black and are called “bladder plums,” “mock plums,” or, most often, “plum pockets.”

Twisting and curling are the most common signs of leaf and fruit infections, but these symptoms may not be present.

If planting new trees, select resistant cultivars. The most effective fungicide practice is a single fungicide spray in late autumn or before spring budbreak. Bordeaux mix, chlorothalonil, and liquid lime sulfur are effective treatments.

Fungicides for Homegrown Peaches and Plums

Captan-containing fungicides with labels for use on residential orchard trees include the following products:

Bonide Captan
Hi-Yield 50 W Captan Fungicide
Southern Ag Lawn and Garden Captan Fungicide

Chlorothalonil

Chlorothalonil-containing fungicides with labels for use on residential orchard trees include these:

Fertilome Broad Spectrum Landscape and Garden Fungicide
Hi-Yield Vegetable, Flower, Fruit, and Ornamental Fungicide
Monterey Fruit Tree, Vegetable, and Ornamental Fungicide
Southern Ag Lawn and Garden Liquid Ornamental & Vegetable Fungicide Contains Daconil

Copper fungicides come in different formulations and brands. Formulations include basic copper sulfate, cuprous oxide, copper hydroxide, and copper octanate. The labels differ depending on the percent of metallic copper in the product. The rates of use should decrease the later in the season the product is to be used to avoid damage to the trees. Check your water pH before using coppers because spraying coppers in water with pH less than 6.5 can result in tree injury. Adjust the water pH using an appropriate spray buffer. Do not apply copper-based fungicides at temperatures greater than 90°F to avoid tree injury. Do not use copper fungicides in conditions that may be overcast with high humidity for 3 or more days.

Copper fungicides with labels for use on residential orchard trees include these:

Bonide Liquid Copper Fungicide Concentrate
Monterey Liqui-Cop
Natural Guard Copper Soap Liquid Fungicide
Southern Ag Lawn and Garden Liquid Copper Fungicide

Myclobutanil

The myclobutanil-containing fungicide labeled for use on residential orchard trees is

Spectracide Immunox Multi-Purpose Fungicide Spray Concentrate for Gardens

Propiconazole

Propiconazole-containing fungicides with labels for use on residential orchard trees include these:

Bonide Infuse Concentrate
Monterey Fungi-Fighter

Sulfur-containing fungicides with labels for use on residential orchard trees include these:

Fertilome Dusting Sulfur
Hi-Yield Dusting Wettable Sulfur
Southern Ag Lawn and Gardend Wettable or Dusting Sulfur

Insect Pests of Peaches and Plums

Plum Curculio

The plum curculio, Conotrachelus nenuphar, is one of the most damaging insect pests of homegrown peaches and plums. The white, legless grubs are the “worms” so often encountered in fruit that has not been adequately protected. Adults are small weevils that overwinter in leaf litter and ground trash in or near the orchard. The adults become active about the time peaches begin to bloom. They fly to trees to feed on buds and newly set fruit females chew crescent-shaped punctures through the skin of developing fruit to insert their eggs. Grubs hatch and feed inside the fruit until mature. Fruit that are attacked when small usually abort, but larger fruit remain on the tree with developing larvae inside. Picking up and destroying fallen fruit can help reduce future infestations. Mature larvae drop to the ground when they are ready to pupate. There are two to three generations per year.

Successful control of plum curculios depends on killing the adults before they are able to lay their eggs in the fruit. Begin including malathion in cover sprays as soon as petals fall and apply on a 10- to 14-day schedule (tighten the spray schedule during rainy periods). Extending the spray intervals will result in reduced control. Tightening spray intervals to 7–10 days, especially for the first few cover sprays, will improve control. The first few sprays after petal drop are the most important because they target the overwintered adults that will lay the eggs for the first generation.

Stink Bugs and Plant Bugs

Several species of stink bugs, as well as tarnished plant bugs, will feed on developing peaches and plums, causing catfacing injury. It is usually adult insects that cause this damage. Their feeding kills developing cells at the feeding site and causes the fruit to be distorted as it grows. Cover sprays containing malathion will usually control catfacing insects. Permethrin is also effective against stink bugs and will control plant bugs in non-Delta areas of the state.

Oriental Fruit Moth

The caterpillar stage of the oriental fruit moth, Grapholita molesta, bores into the terminals, or tips, of peach tree branches, causing them to die back 4–6 inches. This damage is not serious unless populations are high, but once the terminals harden and become unattractive, the caterpillars begin boring into fruit.

The oriental fruit moth is relatively uncommon but can cause significant fruit damage. Watch for early signs of dying terminals and tighten the cover spray interval if necessary to protect fruit. Infested fruit may have masses of gummy sap containing frass at the point of entry. Permethrin can be substituted for malathion if necessary to control heavy infestations.

Peachtree Borers

Two species of peachtree borers attack peaches and plums: peachtree borer (PTB), Synanthedon exitiosa, and lesser peachtree borer, Synanthedon pictipes. Both are wasp-like, day-flying moths whose larvae bore under the bark and tunnel in the cambium. Peach tree borers usually focus their attack on the lower 10–12 inches of the trunk down to the root flare and extending a few inches belowground. Lesser peach tree borers attack higher on the trunk and on lower scaffold limbs. Peach tree borers are the more damaging of these two species.

Moths are especially attracted to trees that have injured areas on the trunk or have previous bore infestations. Keeping trees healthy and protecting trunks and root flares from mechanical injury helps reduce attacks. The eggs are deposited on the surface of the bark, and newly hatched larvae promptly bore into the tree. If PTB are not controlled, trees may die as the result of the cumulative damage caused by larvae tunneling through the cambium. Young, small-diameter trees are especially vulnerable. Balls of gummy sap that contain frass and sawdust indicate bore infestation. Note that some disease infections also cause peach and plum trees to exude gummy balls of sap through the bark. Sap balls that contain frass and/or sawdust indicate a bore problem sap balls that are clear/free of frass and sawdust indicate disease problems.

The key to controlling peach tree borers is to kill the newly hatched larvae before they bore through the bark. This means applying a trunk spray at the proper time of year so the newly hatched larvae have to crawl through the insecticide residue as they bore into the bark. Low numbers of moths may be active in June and July, but cover sprays for other insect pests usually control these. Heavy PTB moth flight does not occur until August and September, usually peaking around early September, and this is the time to apply trunk sprays for peachtree borer control.

Permethrin is currently the best treatment available for peachtree borers in small home orchards. Mix at the highest rate labeled for trunk sprays, and thoroughly spray the lower scaffold limbs, the trunk, and the root flare. Apply a second spray in 2–3 weeks a single application of permethrin will not provide adequate residual control. Treatment dates around mid-August and the first week of September are appropriate for most of the state. To protect trees that are heavily infested or especially vulnerable, make three applications at 2-week intervals, beginning in mid-August.

Granulate Ambrosia Beetle

This tiny beetle occasionally attacks and kills peach and plum trees, as well as many other trees in the home landscape. Actually, it is not the beetle that kills the tree, but the disease it carries and inoculates into the tree. Because they are less than one-eighth of an inch long, the beetles themselves are rarely seen. The sign to look for is the compacted columns of sawdust these beetles create as they bore into the tree. Except for the fact that they are often curved, these sawdust columns are similar to toothpicks in size and color. Be aware, however, that this sign is short-lived, as these sawdust columns are easily broken off by wind and rain.

Even a half-dozen attacks is enough to kill a small tree, and there is no effective rescue treatment. This pest has several generations per year, but most fatal attacks to fruit trees occur in early spring, just as trees are leafing out. These beetles attack many species of trees and shrubs, but peaches and plums seem to be favorite targets, possibly because of pruning activities. Newly planted trees, less than 3 or 4 years old, are most susceptible, but older trees are also attacked.

Fortunately, granulate ambrosia beetle attacks are sporadic they may kill two or three of your seven trees one year and not return for several years. In most situations, there is no practical treatment or response other than to recognize what killed the tree and to cut it down and burn the wood to prevent further spread. To treat preventively, mix permethrin according to label directions for a trunk spray and apply at 2-week intervals, beginning just before buds begin to swell and continuing until just before bloom. Spray to cover the trunk, scaffold limbs, and larger branches. Trees less than 4 years old are most likely to benefit from such treatments. Note that sprays for ambrosia beetles must be applied much higher on the tree than for peachtree borers.

Scale Insects

Heavy infestations of San Jose scale or white peach scale can severely damage peach and plum trees. Scale infestations are difficult to detect because the insects are small and immobile. Watch for irregular, crusty, brown or white patches on limbs and twigs, and then use a hand lens to see individual insects. Scales will also occur on fruit when infestations are heavy. Insecticides used in spring and summer cover sprays help control newly hatched scale crawlers, but dormant horticultural oil sprays are the most effective treatment for scales. Apply a single delayed-dormant treatment in late winter to early spring as a preventive treatment or to control light infestations. Trees that are heavily infested with scales should be treated in late fall, after 95 percent leaf drop and before onset of freezing temperatures, and again in late winter to early spring (delayed-dormant period). Apply spring oil sprays before buds break and new leaf growth is evident. Do not apply oil sprays within 30 days of (before or after) making a spray that contains sulfur.

Irregular, crusty, brown or white patches on limbs and twigs indicate scale infestation. Use a hand lens to see individual insects.

Several species of mites attack peaches and plums. Two-spotted spider mites are the most common, but European red mites and silver mites may also occur. Heavy infestations of spider mites can be damaging and difficult to control because there are no effective miticides labeled for home use. Minimize foliar sprays containing pyrethroid insecticides, such as permethrin, and avoid treatments that contain carbaryl (Sevin) because these treatments tend to encourage spider mite outbreaks. Some mites overwinter as eggs on the bark, and these overwintering eggs can be controlled with a delayed/dormant application of horticultural oil. If heavy mite populations occurred in the previous season, make an application of horticultural oil just before bud break to help reduce the potential for further mite outbreaks.

Protect bees and other pollinators. Avoid spraying insecticides while fruit trees are in bloom. There are no major insect pest problems to be concerned about during this period anyway. Begin your insecticide spray program promptly after petal drop to control overwintered curculios and catfacing insects.

Insecticides for Homegrown Peaches and Plums

Horticultural Oils

Horticultural oils are usually applied in winter to early spring, after leaves drop in the fall and before buds break, to control San Jose scale and white peach scale, as well as overwintering mites. Read and follow the label carefully to avoid injuring plants. Avoid applying horticultural oil sprays when temperatures are below freezing or are likely to drop below freezing for the next 2–3 days. Bonide All Seasons Horticultural Spray Oil and Ortho Volck Oil are two examples.

Malathion is the most effective treatment available to homeowners for controlling plum curculios and is the key insecticide recommended for early cover sprays (beginning at petal fall). Malathion is also effective against immature scale insects (crawler stage) and catfacing insects (stink bugs and plant bugs) and will help control oriental fruit moths and lesser peach tree borers. Examples of brand name formulations include Bonide Malathion Concentrate and Ortho Malathion Insect Spray. The pre-harvest interval for malathion is 7 days on peaches. Avoid applying malathion during periods of overcast or highly humid weather because the spray will dry slowly and increase the potential for plant injury.

Permethrin is a pyrethroid insecticide that controls a wide range of insects. It is the most effective treatment currently available to homeowners for control of peach tree borers. Because overuse of permethrin can trigger outbreaks of spider mites, scales, and aphids, it is not recommended for early cover sprays. Permethrin is effective against oriental fruit moths and catfacing insects, as well as plum curculios, and can be substituted for malathion in one or two of the summer cover sprays. There are many commercial formulations of permethrin that are not labeled for use on peaches and plums. Check labels carefully before you buy. Hi-Yield Lawn, Garden, Pet, and Livestock Spray (10%) and Bonide Total Pest Control Outdoor Concentrate (13.3%) are examples of two products that are labeled for use on peaches. The pre-harvest interval for permethrin is 7 days on peaches.

Pre-Mixed Fruit Tree Sprays

Several companies sell pre-mixed fruit tree sprays. These usually contain a fungicide and one or more insecticides. Malathion should be one of the insecticides. Bonide Complete Fruit Tree Spray Concentrate and Gordon’s Liquid Fruit Tree Spray are two examples (both contain 11.76% Captan, 6% malathion, and 0.3% carbaryl). Such products can be an effective and convenient way to buy and apply pesticides, but read the label carefully before purchasing to be sure the product contains the active ingredients you need. Some “fruit tree sprays” contain active ingredients that are only marginally effective against important insect and disease pests.

Sanitation

A good sanitation program can greatly improve control of diseases and insects. The following sanitation and management practices are simple, inexpensive, and effective:

  • Remove all dead branches and rotted and mummified fruit from trees and the orchard floor.
  • Remove leaves, bark, sticks, and plant debris near trees.
  • Remove any swollen branches from plums.
  • Prune trees properly to allow good air circulation and light penetration.
  • Protect the trunk and root flare area from mechanical injury.

Spray Suggestions

Controlling tree size makes them easier to spray. Pruning reduces tree height and number of limbs. This allows better air circulation and greatly improves spray coverage. Use adequate spray volume for the size of the trees you are treating and take care to get good spray coverage. Apply sprays as a mist of fine droplets with enough pressure to completely cover the tree. Be sure your spray pattern reaches the highest leaves.

Disease spray intervals may need to be tightened during periods of warm, wet weather. Sprays also need to be reapplied, or spray intervals tightened, following rainfall of a half-inch or more. Never use a sprayer for peach and plum trees that has been used to apply 2,4,D weed killers.

Be careful when applying pesticides. Always follow all label recommendations and restrictions.

Number of Gallons of Spray Required, Based on Tree Size

Spray Schedule to Control Diseases and Insects

Read pesticide labels carefully and observe all directions and restrictions.

Time of Application

Material to Use per Gallon of Water

Dormant (before buds swell in spring)

Peach leaf curl and bacterial spot

2 cups liquid lime sulfur
Apply copper fungicide at the bacterial spot rates.

Delayed dormant (1–5% bud swell)

If leaf curl or plum pockets are a problem

Beginning of bloom (pink to 5% bloom)

If bacterial spot is present

2 tbsp Captan2 50% WP (fungicide)

If brown rot was a problem the previous year

Captan2
or
Chlorothalonil3

Petal fall to start of shuck split (after ¾ or more of the petals have fallen)

For disease control:

2 tsp malathion 50% EC (insecticide) 3

Summer cover sprays (beginning at shuck fall4 and at 10- to 14-day intervals until harvest shorten spray intervals if there are frequent rains)

For disease and insect control:

2 tbsp Captan2 50% WP + Spectracide Immunox5 ½ fl oz
or
propiconazole5 (fungicide)5

Post-harvest (mid-August and early September)

Permethrin trunk sprays for peach tree borers mix per label directions. Apply two to three sprays at 2- to 3-week intervals.

Early dormant (late fall after leaf drop and before freezing temperatures)

Chlorothalonil3 or lime sulfur especially needed if peach leaf curl or plum pockets have been a problem.

WP – wettable powder
tbsp – tablespoon
EC – emulsifiable concentrate
tsp – teaspoon

1 The rate of copper must be reduced as the season progresses otherwise, tree injury (phytotoxicity) may result. Carefully follow label directions. Copper antibacterial activity and phytotoxicity are related to the pH of the water used to dilute the fungicide. Water pH less than 6.5 may increase the risk of phytotoxicity. If necessary, adjust the pH of the water before mixing.

2 Do not apply Captan within 14 days of an oil spray (as in horticultural oil). Captan may cause leaf spotting if leaves are drenched (excess solution applied to leaves) or if leaves do not dry for a long period.

3 Do not tank mix chlorothalonil with an EC formulation of any product, such as malathion EC. Tree injury will result.

4 Shuck fall is the stage when all flower parts have fallen from the newly formed fruit. It occurs 5–7 days after petal fall.

5 Do not apply myclobutanil (Spectracide Immunox) OR propiconazole (Bonide Infuse or Monterey Fungi-Fighter) in any combination more than seven times per season for brown rot control.

Home orchardists are sometimes discouraged by the number of disease and insect treatments it takes to make a good crop of unblemished fruit. “I just want to be able to make a few peach cobblers every year. Can I get by with spraying less if I am willing to accept lower yields and some damaged fruit? If so, which sprays are most important?”

For insect control, the most important sprays are the three to four curculio sprays beginning at petal fall. The goal is to control the overwintered adults before they can establish an infestation. These sprays will also control catfacing insects. It’s also important to spray for peachtree borers in August and September to protect your trees from these pests. Treat for scale and other insects as needed.

Cutting back on disease control sprays is risky. If a disease gets established during the season, the consequences can be severe and long lasting. The most important treatments are the dormant sprays and sprays through flowering. You can reduce fungicide sprays by applying fewer cover sprays during periods of dry weather.

The information given here is for educational purposes only. References to commercial products, trade names, or suppliers are made with the understanding that no endorsement is implied and that no discrimination against other products or suppliers is intended.

Before purchasing and using any pesticide, always carefully read the label to make sure the product is labeled for the intended use.

Carefully follow all instructions and restrictions specified on the product label.

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By Blake Layton, PhD, Extension Professor, Biochemistry, Molecular Biology, Entomology, and Plant Pathology, and Alan Henn, PhD, Extension Professor, Biochemistry, Molecular Biology, Entomology, and Plant Pathology.

The Mississippi State University Extension Service is working to ensure all web content is accessible to all users. If you need assistance accessing any of our content, please email the webteam or call 662-325-2262.


Managing Wood-boring Insects

Prevention
Since most wood-boring insects are considered secondary invaders, the first line of defense against infestation is to keep plants healthy. Proper care of trees and shrubs discourages many borer pests and helps infested plants survive. Good sap flow from healthy, vigorously growing trees, for example, defends the plant from damage by many borer pests. Good horticultural practices include:

  • Selecting well adapted species of trees and shrubs that are not commonly attacked by wood borers in your area. Arizona ash, birch, cottonwood, locust, soft maple, flowering stone fruits (such as peaches and plums), slash pines (in west Texas), willow and poplar are especially prone to borer attack.
  • Choosing and preparing a good planting site to avoid plant stress, freeze damage, sun scald and wind burn.
  • Minimizing plant stress and stimulating growth by using proper watering and fertilization practices.
  • Avoiding injury to tree trunks from lawn mowers, weed trimmers or construction.
  • Promptly caring for wounded or broken plant parts using pruning or wound paint during all but the coldest months of the year.
  • Properly thinning and pruning during colder months.
  • Removing and destroying infested, dying or dead plants or plant parts, including fallen limbs. Wrapping tree trunks and limbs with quarter inch hardware cloth spaced about 1 ½ inches from the tree’s surface where woodpecker damage is likely.

Wrapping trunks to prevent borer attack is ineffective and may, under certain conditions, increase the rate of infestation. Using plastic trunk protectors to help prevent injury from lawn mowers and weed trimmers is a good idea.

Non-chemical control for infested plants

Once trees and shrubs are infested, non-chemical options for borer control are limited. One option is to remove and destroy heavily infested or injured plants. Also, inspect damage sites closely to determine if the larvae can be extracted from the plant with a pocket knife, wire or other suitable tool.

Chemical control

Because stressed, unhealthy trees are more susceptible to insect attack, maintaining overall tree health is vital in reducing the risk of wood-boring insect infestations and limiting the need for costly and environmentally damaging insecticides. Older trees and those damaged by drought or other environmental stress also will not benefit from control efforts.

Table 1 lists some insecticides registered by the Environmental Protection Agency (EPA) for wood boring insect control on trees and shrubs. Some of these products are for professional or commercial use only and not available at retail outlets. In addition, the product labels specify where the product is to be used, such as nurseries or landscapes, and which pest or pest category it targets. Choose products according to the labeled restrictions. Do not use insecticides on fruit or nut trees unless specifically labeled for them. Some products sold mainly through specialty stores may require the purchaser to have a Texas Department of Agriculture pesticide applicator’s license.

Application timing and method also may be specified on the label. Some products are preventive only others are to be used during the target pest’s adult flight periods. Bark sprays target egg-laying females or the adult stages emerging from the host plant. They also may kill small larvae. Bark sprays generally use residual insecticides such as carbaryl or pyrethroid insecticides such as bifenthrin or permethrin. Only a few products are effective on larvae tunneling beneath the bark, such as that of the flatheaded borer beetles. These systemic products usually are applied as soil drenches so the insecticide can be absorbed by the roots or injected into the trunk the insecticide imidacloprid is applied as either a soil drench or a trunk injection. Dinotefuran also may provide some control of wood-boring beetles.

Retail sale of diazinon, chlorpyrifos (Dursban®) and endosulfan (Thiodan®) products have been discontinued. Diazinon and lindane are no longer available for insect control and chlorpyrifos is available only for use in commercial nurseries. Products containing these ingredients may still be used according to label directions if you first contact the manufacturer to ascertain that usage is allowed. Otherwise they should be disposed of using directions provided by city, county or state pesticide authorities.

Only a few products for controlling wood-boring insects are available at retail stores. Occasionally these products’ containers have labels that are taped to the container and cannot be read before purchase. The products’ names may indicate target pests, such as Fertilome® Borer, Bagworm, Tent Caterpillar & Leafminer Spray, but the actual label has use directions for only the peach twig borer (a caterpillar of a clearwing moth species) on fruit trees. In other cases, lists of pests on products that are available only to commercial applicators are more extensive than those on products available to homeowners, such as those containing the pyrethroid insecticides, bifenthrin and permethrin.

Know pesticide regulations. Insecticide use is regulated by the Environmental Protection Agency’s Federal Insecticide, Fungicide, and Rodenticide Act (https://www.epa.gov/pesticides) and Texas Department of Agriculture.

  • The law mandates that pesticides be used according to label directions with a few exemptions: An user can use an insecticide for pests not listed on the product label as long as the use site is listed. Section 2(ee) of FIFRA (page 13) allows for the use of any registered pesticide “against any target pest not specified on the labeling if the application is to the crop, animal, or site specified on the labeling…” Thus, if a particular insect borer is not listed on a product labeled for use on trees and shrubs but others are listed, or other products include mention of those pests, that product may be used to try to control the unlisted pest.
  • Some products claiming insect control now being sold may not be registered by the EPA because of an exemption described in Section 25 (b) (on page 89 and on the Web site https://www.epa.gov/pesticide-registration/pesticide-registration-notices-year). Only those pesticides registered by the EPA are listed in this publication.

Firewood
Adult wood borers sometimes emerge from firewood stored indoors. While most of these insects are not considered harmful, old house borer and powderpost beetles will attack seasoned, dry wood inside the home (see the Texas AgriLife Extension Service publication E-394, “Structure-Infesting Wood-Boring Beetles”). Treating firewood with insecticide is both ineffective and potentially dangerous to the homeowner. Wood should be stored outdoors away from the house until just before use. If firewood is infested with borers it can be treated by wrapping it in a tarp and allowing sunlight to heat it. Stacking wood layers in alternate directions will help it dry and reduce areas that can harbor insects. Firewood can spread exotic wood-borer species. Do not transport firewood to new areas, such as out-of-state camp grounds. Obtain campfire wood locally for use on such occasions.


Homemade Spray for Peach Tree Borers?

by Charlotte
(Southern,California,USA)

Have spots on my peach tree,that have a clear jelly-like blobs on the branches. I was told it's peach tree borers.

Is there a homemade spray I can make to kill them without hurting/damaging my tree?

A homemade spray for peach borer that I would recommend would be neem oil. This is because one of the most successful ways of getting rid of peach borer is done by interrupting the mating cycle. Neem oil does exactly this.

However, you also need to know when the peach borer attacked your tree and the cycle times to be able to interrupt that cycle.

Female borers start out in the summer looking for trees to lay their eggs in. In northern areas this is generally in July, for southern areas this is usually August and September.

Peach borers like to lay their eggs on tree trunks a few inches below the soil line, at the soil line and to about a foot above the soil line.

Some species, such as the lesser peach tree borer will lay their eggs in damaged areas of the upper tree limbs.

Borers produce one generation per year.

When you apply your neem oil spray, you will need to apply it to all these areas to be successful.

The peach tree larva hatch and as soon as cooler weather arrives they go into a rest period for the summer. As soon as the weather warms up in the following season they are ready to feed and do their damage.

Now, you can make your own neem homemade spray if you are lucky enough to live in a tropical or sub-tropical area where you have access to neem trees. However, more often than not you will need to go to your garden center and see if you can buy a commercial product. There are several now that are available.

Neem oil is definitely one of the best natural pesticides around.

If you don't have access to neem oil, then the other alternative is to take wire, poke the holes out as much possible and then make a solution of Diatomaceous Earth and fill the holes with this. You can either use a syringe to do this, or you can reduce the water and just pack it into the holes. Complete this by using window putty or plastic wood to seal the hole.

Some people also plant garlic at the base of their peach trees to discourage peach borers. I prefer to use a mixture of garlic and tansy. Here I am talking about the common tansy, not tansy ragwort.

Tansy not only helps to keep peach borer and other flying insects away, it also concentrates the potassium in the soil, so is beneficial to the peach trees from that aspect as well, as its presence will help fertilize the fruit trees.

And while I am espousing the virtues of tansy it is great companion planting with potatoes to ward off the Colorado potato beetle.

However, common tansy is midly toxic to so please keep your small children, chickens and other livestock away from this herb.

People do drink tansy tea as a worm remedy, and during the pioneer days tansy was rubbed onto the meat to help preserve it. However, it is very bitter to the taste, and most animals will find it unpalatable, but don't feed it directly to your chickens as you would stinging nettles , for example.


How to Manage Pests

Apricot

Peach Twig Borer

Scientific name: Anarsia lineatella WEATHER/degreedays/index.html

(Reviewed 10/14 , updated 10/14 , corrected 10/16 )

DESCRIPTION OF THE PEST

The peach twig borer is widely distributed throughout California and is found on several hosts. The adult moth is about 0.3 to 0.5 inch long, with steel gray, mottled forewings. Young larvae are almost white with black heads. Mature larvae are about 0.5 inch long and have black heads and dark brown bodies with white portions between each body segment, giving the appearance of stripes. The peach twig borer overwinters as a larva in a tiny cell called a hibernaculum, located in limb crotches of 1- to 4-year-old wood or in roughened areas of the trunk. There may be three to four generations each year, but the later generations occur after apricot harvest.

DAMAGE

This pest damages in two ways. Larvae burrow down into tender shoots and kill the tip, which may cause problems in training young trees. They also feed on fruit, primarily at the stem end (early-harvested varieties are less susceptible than later-harvested ones). Either feeding damage or the presence of larvae will cause a fruit to be offgrade.

MANAGEMENT

Within an IPM program, the preferred management strategy for peach twig borer is well-timed treatments of environmentally sound insecticides around bloom. These include Bacillus thuringiensis, spinosad (Entrust, Success), and diflubenzuron (Dimilin). Bloom applications integrate well with brown rot treatment, thus helping to cut application costs. Bloom sprays are preferred over in-season sprays in an IPM program because they harm beneficials and nontarget organisms less and do not leave residue on fruit.

Alternatively, peach twig borer can be controlled with a dormant insecticide spray of oil plus spinosad (Entrust, Success), Intreprid, or diflubenzuron (Dimilin) to kill overwintering larvae in the hibernacula. Oil plus an organophosphate or pyrethroid insecticide is the most environmentally disruptive dormant spray option, as it raises water quality concerns and may pose some risks to raptors, aquatic invertebrates, beneficials, and other nontarget organisms. Dormant sprays of oil alone or oil combined with an effective insecticide have the advantage of controlling some other stone fruit pests, especially mites and San Jose scale. Oil alone does not control peach twig borer, and some apricot cultivars are sensitive to dormant oil sprays. Mating disruption can also be used effectively in early harvested orchards to supplement dormant sprays.

Mating disruption

Mating disruption with sex pheromones can be used to supplement dormant or bloom sprays. The main practical use for mating disruption is where the crop is harvested before July and in organic systems. For later-harvested fruit, mating disruption has not been reliable against peach twig borer when used alone and should be supplemented with a bloom treatment of Bacillus thuringiensis or spinosad.

Mating disruption is most effective in orchards with low moth numbers that are not close (a mile) to other untreated peach twig borer hosts or almond orchards. Efficacy is reduced by small orchard size (especially if located near outside sources of moths if a small orchard is isolated, then size is not a major factor), uneven terrain, reduced pheromone application rates, applying too low in the tree, improper timing, and high insect pressure. Follow timing guidelines given in the treatment table below.

Biological Control

Peach twig borer has about 30 species of natural enemies. The gray field ant, Formica aerata, preys on peach twig borer during spring and summer. In some years these natural enemies destroy a significant portion of larvae, but by themselves they generally do not reduce twig borer numbers below economically damaging levels. Other commonly found natural enemies in California are the chalcid wasps, Paralitomastix varicornis and Hyperteles lividus, the braconid wasp Macrocentrus ancylivorus, and the grain or itch mite, Pyemotes ventricosus.

Organically Acceptable Method

Use sprays of Bacillus thuringiensis, sprays of the Entrust formulation of spinosad, and hand-applied mating disruption during bloom for peach twig borer management on organically grown apricots.

Monitoring and Treatment Decisions

Degree-days

Calculate degree-days for peach twig borer in your location.

Learn to use degree-days to time insecticide applications.

Before bloom

Delayed dormant applications target the overwintering larvae in hibernacula and are best applied immediately before bloom. Spinosad (Entrust, Success) or diflubenzuron (Dimilin) pose less risk to water quality and provide the same level of control as organophosphate or pyrethroid insecticides. These can be combined with red bud fungicide sprays, but the preferred management strategy is well-timed applications of environmentally sound insecticides at bloom.

Bloom.

Monitor peach twig larvae during bloom and when shoots are emerging. Look for feeding at the base of flowers. Damaged shoots do not wilt therefore damage may not be obvious.

If larvae or their damage are observed at this time, two sprays of Bacillus thuringiensis (Bt) or a single treatment of spinosad (Entrust, Success) or diflubenzuron (Dimilin) can be applied. Bt sprays at bloom can also be timed by dissecting hibernacula regularly from late February through bloom. Look at young trees or 1- to 4-year-old wood near branch crotches to detect the tiny hiberncula. The increase in the number of empty hibernacula reflects the number of larvae that have emerged and can be controlled by Bt once foliage is present.

Sprays for peach twig borer are often combined with sprays for powdery mildew and brown rot.

In-season

If delayed dormant or bloom sprays were not applied or if numbers are high, an in-season spray may also be needed. Install pheromone traps in orchards by March 15 in the San Joaquin Valley and Central Coast and April 1 in the Sacramento Valley. Results from trap catches and degree-day accumulations are used to determine the timing. Once the first moth has been trapped, begin accumulating degree-days (DD) using a lower threshold of 50°F and an upper threshold of 88°F.

Research has shown that best control can be achieved when treatments are applied about 400 DD from the beginning of the flight if the fruit is still green if fruit has begun to color, treat at 300 DD. If Bacillus thuringiensis is used, however, two sprays should be applied: one at 300 to 350 DD and the other at 450 to 500 DD.

Take weekly fruit samples after color break to detect any developing problems in the orchard and a fruit damage sample at harvest to assess the effectiveness of the current year's IPM program and to determine the needs of next year's program (see FRUIT SAMPLING AT HARVEST). Record results (example form— PDF ).

IMPORTANT LINKS

PUBLICATION

UC IPM Pest Management Guidelines: Apricot
UC ANR Publication 3433

Insects and Mites

W. W. Coates, UC Cooperative Extension, San Benito County
R. A. Van Steenwyk, Insect Biology, UC Berkeley
W. J. Bentley, UC IPM Program, Kearney Agricultural Center, Parlier
K. R. Day, UC Cooperative Extension, Tulare County
K. A. Kelley, UC Cooperative Extension, Stanislaus County
J. L. Caprile, UC Cooperative Extension, Contra Costa County

Acknowledgment for contributions to Insects and Mites:

Statewide IPM Program, Agriculture and Natural Resources, University of California
All contents copyright © 2019 The Regents of the University of California. All rights reserved.

For noncommercial purposes only, any Web site may link directly to this page. FOR ALL OTHER USES or more information, read Legal Notices. Unfortunately, we cannot provide individual solutions to specific pest problems. See our Home page, or in the U.S., contact your local Cooperative Extension office for assistance.

Agriculture and Natural Resources, University of California


Watch the video: Peach Tree Borers This Week In the Garden