Bradford pear leaf disease

Pear Tree Diseases And Treatment: Diagnosing And Treating Disease In Pears

Home-grown pears are really a treasure. If you have a pear tree, you know just how sweet and satisfying they can be. Unfortunately that sweetness comes at a price, as pear trees are susceptible to quite a few easily spread diseases that can wipe them right out if left untreated. Keep reading to learn more about pear tree diseases and treatment.

Common Diseases of Pears

There are a few very common and easily identifiable diseases of pears. Of these, fire blight is the worst, as it can spread very rapidly. It appears as cankers that leak out a creamy ooze on any or all parts of the tree, blossoms, and fruit. The area around the canker takes on a blackened or burned appearance, hence the name.

Fabraea leaf spot, leaf blight, and black spot are all names for a spread of brown and black spots that form on the leaves late in the summer and cause them to drop. The spots can also spread to the fruit.

Pear scab manifests itself as soft black/green lesions on the fruit, leaves, and twigs that turn gray and crack with age. Outbreaks occur once in early summer and again in mid-summer.

Sooty blotch appears as black smudges on the skin of the fruit. Be on the lookout for sick looking pear trees, especially during wet spells, as most types of pear tree disease appear and spread during periods of rain and high humidity.

How to Treat Sick Looking Pear Trees

The most effective method for treating disease in pears is the sanitation and removal of all affected parts of the tree.

If your pear shows signs of fire blight, cut away any branches exhibiting symptoms 8-12 inches (20-30 cm) below the canker, leaving only healthy wood. After each cut, sanitize your tools in a 10/90 solution of bleach/water. Take the removed branches far from your tree to destroy them, and monitor your tree for any new cankers.

For both leaf spot and pear scab, remove and destroy all fallen leaves and fruit to greatly reduce the risk of the disease’s spread into the next growing season. Apply a fungicide throughout the next growing season as well.

Sooty blotch affects only the appearance of the fruit and will not harm your tree. It can be removed from individual pears with scrubbing, and the application of fungicide should curb its spread.

Since these diseases spread through moisture, a lot of preventative work can be done simply by keeping the surrounding grass short and pruning the tree’s branches to allow for air circulation.

Fabraea Leaf Spot

Overview

  • Fabraea leaf spot is a fungus (Diplocarpon mespili) that infects primarily leaves and fruit of pear and quince. Infections can result in significant leaf spotting, defoliation, and unmarketable fruit.
  • Fabraea leaf spot infection occurs from spring to summer, and like apple scab, spores are released and spread during periods of rainfall.
  • Sanitation by flail mowing leaves and brush may help reduce Fabraea leaf spot spores, however, chemical control is still usually necessary.
  • Chemical control using contact fungicides beginning in the spring and continuing into the summer in wet years are necessary to control Fabraea leaf spot.

Symptoms & Signs

Fabraea most noticeably first manifests itself as small, purple-black spots on leaves and fruit. Spots gradually enlarge into brown lesions 1/8 to ¼ inch in diameter. When the infection is severe, defoliation can occur and fruit will become deformed and not sellable and/or drop off the tree. Fabraea may also infect shoots, again appearing initially as purplish spots, becoming lesions/cankers which may persist into the next growing season. Leaf and fruit infections are most notable in the Northeast and Midwest, but in the Southeast , shoot infection can be significant. Severe infections can result in reduced flower bud formation for the following season.

Disease Cycle

Similar to apple scab, much Fabraea overwinters in leaves on the orchard floor. Farther south, overwintering is also likely to occur in shoot cankers. Spores are released from leaves with rain from mid-May to July (in the Northeast and Midwest) and result in primary infection on fruit and foliage. Shoot cankers spread Fabraea from late-April through May (in the Southeast) with more driving rains. Length of wetting for infection to occur can range from 12 hours at 50 degrees F. to as little as 8 hours from 68 to 77 degrees F. Infections take about 7 days to become visible. Once primary infection occurs, secondary infection can spread rapidly with rain and wind during the summer, particularly during wet seasons.

Chemical Control

Contact/protectant fungicides are necessary to control Fabraea leaf spot. EBDC fungicides (Manzate, Penncozeb, Dithane) and Ziram give good control. (But EBDC’s have a 77 day Pre-Harvest Interval.) Early season fungicide application(s) for pear scab (as long as EBDC’s or Ziram are included) will prevent initial infection by Fabraea. Where disease pressure is high, however, summer-long fungicide applications (once the pear scab season has passed) will be required, particularly in wet summers. Late-maturing varieties may even need fungicide sprays into the early fall to prevent Fabraea from infecting fruit.

Fungicide Resistance in the Eastern U.S.

None known because contact fungicides are necessary for control.

Non-Chemical Control

Biological Control

Other than sanitation, there is no known biological control of Fabraea leaf spot.

Cultural Control

Flail mowing/chopping leaves and brush and removing obvious cankers on the tree may help to control Fabraea leaf spot and is recommended.

Resistant Varieties

Although there are some variety differences in susceptibility to Fabraea leaf spot, generally just consider the fact all European pear varieties are susceptible such that the disease will need to be controlled. Bosc and Seckel, however, appear to be especially susceptible to Fabraea.

Links

Pear scab

Note Number: AG0159
W.S. Washington and Oscar Villalta, Knoxfield
Updated: January 2006

Pear scab, or black spot, is caused by the fungus Venturia pirina. It infects leaves, shoots, blossoms and fruit, and can cause serious crop loss especially in wet seasons when control measures are inadequate. The disease is found world-wide, wherever pears are grown. The fungus is closely related to apple scab, but although many similarities exist, cross-infection from one host to the other cannot occur.

Symptoms

The symptoms of pear scab are very similar to those of apple scab. Fruit infections appear as olive-green to black spots. Early infections cause large spots that distort the fruit while later infections cause smaller, more superficial spotting. As with apple scab, infections immediately before harvest may produce storage scab i.e. very small black spots that develop on fruit during storage. Leaf infections, which are less common than in apple scab, frequently occur on the underside of leaves. Twig infections, by contrast, are more common than on apple, and appear as small oval blisters on the affected shoot .

Figure 1. Winter Nelis fruit infected with pear scab, showing spotting and fruit distortion

Economic importance

Pear scab is the most serious and widespread fungal disease of pears. Losses from the disease are similar to those caused by apple scab on apples, and control depends mainly on costly spraying programs

Disease cycle

Figure 2. Pear scab lesions on underside of leaf

The disease cycle of pear scab is similar to that described for apple scab. The main difference is that under Victorian conditions shoot infections on pears are more common than on apples. These shoot infections can provide the fungus with another means of overwintering, although overwintering as ascospores in dead leaves under trees is still the most important source of primary inoculum. Shoot infections are common on Winter Nelis and Beurre Bosc, but are less common on Williams’ Bon Chretien and Packham’s Triumph.

Infection periods (the time that leaves or fruit must remain wet for infection to occur) of pear scab are similar to those described for apple scab, although few detailed studies have been carried out to confirm this.

Control measures

Principles of control are very similar to those for apple scab. Control is based on a protectant spray program, supplemented by post-infection and autumn eradicant sprays. The period from delayed green tip to petal fall is most important in preventing infection. This corresponds with the period of greatest discharge of ascospores. Apply the first spray when one-third of buds reach the stage of delayed green tip. Apply the second spray about five to seven days later, and the third spray about 10 to 14 days after the first. A fourth spray should be applied at petal fall. Growing plant tissues could become exposed during infection periods in showery weather, and a fifth spray may be needed between delayed green tip and petal fall. Alternatively a post-infection spray may be needed.

Cover sprays applied at 10-14 day intervals after petal fall may be necessary if primary infection has occurred, and if wet weather favourable to infection persists. During dry summer weather no further sprays are necessary. However, if an infection period does occur, the use of an appropriate protectant spray before the wet period, or a post-infection spray shortly after it, should prevent development of summer scab.

Similarly, infection periods immediately before harvest may make sprays necessary in order to prevent the development of scab in storage.

Note that post-infection sprays must be applied within several days of an infection period. For maximum effect they should be applied as soon as the weather clears after such a period.

When scab has been difficult to control, use sanitation practices after harvest to reduce the carryover of the fungus into the next season. Some practical sanitation practices are:

  • treating leaves on the tree immediately before leaf fall with a nitrogenous fertiliser to hasten leaf breakdown
  • mulching the leaf litter after leaf fall by sweeping and then using a mechanical shredder, slasher or flail mower to chop leaves into small pieces which then break down more rapidly
  • combining leaf mulching with a ground application of a nitrogenous fertiliser.

When planning your scab spray program, it is wise to include at least two fungicides with different modes of action. This minimises the risk of development of resistance to fungicide. Consult with chemical resellers for the fungicides and spray timing that is most appropriate in your situation.

Monitoring potential overwintering scab

Check levels of leaf infection in all blocks after harvest to estimate the potential level of scab which may overwinter and initiate primary infection in the following spring.

For effective pest and disease control, correct diagnosis is essential. Phone Crop Health Services on (03) 9032 7515 or fax (03) 9032 7604.

The previous version of this note was published in December 1999.

The advice provided in this publication is intended as a source of information only. Always read the label before using any of the products mentioned. The State of Victoria and its employees do not guarantee that the publication is without flaw of any kind or is wholly appropriate for your particular purposes and therefore disclaims all liability for any error, loss or other consequence which may arise from you relying on any information in this publication.

Which are the Best Pear Trees?

pear tree image by Liz Van Steenburgh from Fotolia.com

There are three main groups of pear trees (Pyrus spp.), according to Texas A&M University. European pears have soft, juicy flesh. Asian pears are crispier and are often called “apple pears” for their resemblance to apples. Oriental pears are hybrids. Some varieties of these pear trees produce fruit, while others are only ornamental. Which of these you consider to be the best depends in large part on your reason for choosing to grow a pear tree. Still, there are some that are considered to be hardier and easier to grow than others.

“Summercrisp”

Pyrus “Summercrisp” is a very strong pear tree cultivar. This tree’s heritage is not known, although it tends to resemble Asian pear trees over European pears. This pear tree is an excellent choice for home gardeners who live in cold climates, as it is very cold-hardy. Summercrisps can tolerate temperatures to 50 degrees below zero Fahrenheit, according to the University of Minnesota.

Summercrisp pear trees are also one of the earliest flowering pear trees, making them an attractive choice in landscapes that are barren of early spring color. The trees are on the smaller side, averaging only 18 feet tall, which is another reason why they are good in home gardens. Finally, Summercrisp pear trees are free of most insect pests and diseases, including the fatal fire blight disease. Summercrisp pears should be eaten right off the tree or refrigerated immediately. They should and not allowed to ripen off the tree or become soft or they might develop an unpleasant odor.

Warren

“Warren” is the best Oriental hybrid in terms of fruit quality and resistance to fire blight, according to Texas A&M University. The pears are very smooth, not gritty, and are excellent baked, canned or eaten raw. The fruit size is small or medium, with a faint red tinge. The pears are harvested in August.

“Beierschmidt”

“Beierschmidt” is a very hardy European pear variety. The pears are large, with long necks and golden yellow skin. The skin is thin and the flesh is very tender. This is one of the best pear trees if you want sweet, juicy, melting pears to eat raw. The pears are top quality fruit and are harvested in September.

“Luscious”

“Luscious” pear trees are also excellent for cold climates. This hardy, fire-blight-resistant European pear can tolerate northern climates and produces very large, very sweet pears. The pears, which are harvested in mid-September, are not ripe until they have been stored for a week to 10 days. They can last up to two weeks and still be good to eat, making this one of the best pear trees for home gardeners who want to store or gift their pears.

Connecticut State The Connecticut Agricultural Experiment Station

Disease Control for Home Pear Orchards

PP022 (11/03R)
By Dr. Sharon M. Douglas
Department of Plant Pathology and Ecology
The Connecticut Agricultural Experiment Station
123 Huntington Street
P. O. Box 1106
New Haven, CT 06504-1106
Telephone: (203) 974-8601 Fax: (203) 974-8502
Email: [email protected]
There are a number of diseases that commonly occur year after year in both commercial and home plantings of pears. These diseases do not infect at the same time but appear in a fairly regular sequence depending on the weather and the development or phenology of the pear host, beginning at dormancy and continuing until fruit are harvested. Consequently, a season-long program for disease management is often necessary in order to harvest a high percentage of useable fruit. The diseases that are common in pear include fire blight, pear scab, Fabraea leaf spot, and sooty blotch. Weather conditions greatly influence both the occurrence and severity of plant diseases. Therefore, diseases are generally most difficult to control in years of prevailing high temperature, high humidity, and abundant rainfall and cloudcover.

I. CONTROL STRATEGIES

Pear diseases can be effectively managed through the combined use of culture, sanitation, resistance, and fungicide sprays. This integrated approach to disease control minimizes the reliance upon one type of control over the others and usually results in a high percentage of quality fruit.

A. Culture:

Cultural methods include maintaining tree vigor by proper planting, fertilizing, and pruning and by following general practices that help to minimize tree stress.

B. Sanitation:

Sanitation involves pruning and removing affected or dead portions of the tree and removing diseased foliage or fruit, which are often important sources of inoculum for the next season.

C. Resistance:

Resistance involves selection and planting of varieties with genetic resistance to specific diseases. This effectively reduces or eliminates occurrence of the disease in question.

D. Fungicide Sprays:

Proper selection, timing, and application of these sprays are important. Thorough coverage of all parts of the tree is necessary and sprays should be applied until runoff. The fungicide label will contain information on plant hosts and diseases, dosage rates, days-to-harvest intervals, and safety precautions.

II. COMMON DISEASES

A. Fire Blight:

Fire blight, cause by the bacterium Erwinia amylovora, is the most devastating disease of pear. Fortunately, this disease is not a problem every year and, when it does occur, it is often isolated to specific geographical locations. However, when infection occurs, the disease develops quite rapidly and can destroy individual trees or even orchards in a single season.
The bacteria survive the winter in old cankers on pears and other plants and in healthy pear buds. This disease can occur in four phases: canker blight, blossom blight, shoot blight, and trauma blight. As the weather becomes favorable for growth in the spring, the bacteria begin to multiply rapidly and can be seen oozing out of tissues. This creamy, bacterial ooze is attractive to insects and they pick it up and carry it to open flower buds where infection occurs. The bacteria are also carried by wind and rain to open pear blossoms. Infected tissues are characterized by their blackened, “burned” appearance, hence the name “fire blight.”
The most effective method for control of this disease in home plantings is sanitation. Any cankered or infected branches or twigs should be cut back to healthy wood during the dormant season. All pruning cuts should be made at least 8-12″ below visible symptoms. All tools should be disinfested with 10% bleach (1 part bleach: 9 parts water) or 70% alcohol. Prunings should also be removed from the vicinity of the tree. In addition to these practices, it is important to scout for new infections and remove blighted tissues as soon as they appear. The effects of this disease can also be minimized by maintaining overall tree health by following proper cultural practices that avoid excessive vigor. Pear cultivars vary with regard to their overall susceptibility to fire blight, so “less susceptible” cultivars (e.g., Comice, Winter Nelis) can be selected for planting.

B. Fabraea Leaf Spot:

Fabraea leaf spot, also known as leaf blight and black spot, is caused by the fungus Fabraea maculata. This disease usually appears late in the growing season but can occasionally develop in late May and early June. Fabraea leaf spot attacks leaves, fruit, and twigs of pear. Symptoms first appear as brown to black spots on the leaves. Heavily infected leaves often yellow and drop prematurely. Severe defoliation can substantially reduce tree vigor and yield, especially if trees are defoliated several years in a row. Lesions on fruit appear similar to those on leaves but become slightly sunken as fruit expand. Severely infected fruit may also crack. Once established in a tree or planting, this disease is difficult to control since significant amounts of fungal inoculum overwinter on infected leaves. Spores of the fungus are easily spread by splashing rain and wind in the spring.
Effective control includes a good sanitation program. Since overwintering infected leaves are a major source of spores in the spring, removal of all fallen leaves during the dormant season significantly reduces the chances for new infection. In addition, properly selected and timed fungicide sprays are important for disease control (refer to Spray Guide below).

C. Pear Scab:

Pear scab, caused by the fungus Venturia pirina, is a disease that is quite similar to apple scab. The fungus causes circular, velvety, olive-black spots on leaves, fruit, and sometimes twigs. As the lesions age, they become gray and cracked. The fungus overwinters on dead, fallen leaves and produces spores (primary) in the spring that can infect during periods of rain. Infection from these primary spores can take place anytime after pear growth begins until mid to late June if suitable weather conditions exist. During the summer, a different spore (secondary) is produced by the fungus that is capable of inciting more new infections when splashed onto leaves and fruits by rain.
This disease is effectively controlled by a good sanitation program in which diseased leaves and fruit are removed from the vicinity of the tree. This significantly reduces sources of inoculum in the spring. Scab can also be controlled with properly selected and timed fungicide sprays (refer to Spray Guide below).

D. Sooty Blotch:

Sooty blotch, caused by the fungus Gloeodes pomigena, is recognized by black, sooty smudges on the surface of pear fruit. This disease is particularly severe when rainy weather occurs early in the season and continues into the summer. Sooty blotch develops gradually during periods of high humidity. It is favored by frequent showers, prolonged cloudy weather, and poor air circulation.
Since the fruit infections are superficial, they can often be removed with vigorous washing and rubbing. In addition, practices that promote air circulation, such as pruning and mowing the grass around the tree, are usually enough to keep this disease in check. Fungicide sprays can be applied if the tree has a history of severe disease and blemish-free fruit are important (refer to Spray Guide below).

III. SPRAY GUIDE

A. Pesticides:

Several fungicides are effective for control of many of the common diseases of pear. These include:
1. Ferbam: used alone or in combination with thiophanate methyl for control of scab, Fabraea leaf spot, and sooty blotch.
2. Mancozeb: for control of scab and Fabraea leaf spot.
3. Thiophanate methyl: use in combination with mancozeb or ferbam for control of scab, sooty blotch, and Fabraea leaf spot.

CAREFULLY READ THE LABEL ON EACH PESTICIDE BEFORE USE!!!

B. Spray Schedule:

GROWTH STAGE

DISEASE

MATERIALS/CULTURE

DORMANT: during the winter or dormant season

Fire blight

Prune any cankers or infected wood at least 12″ below symptoms; disinfest tools

GREEN CLUSTER BUD: after the blossom buds are fully exposed but before they separate from the cluster

Scab and Fabraea leaf spot

Thiophanate methyl in combination with mancozeb, or mancozeb

WHITE BUD: approximately 7 days after Green Cluster Bud

Same as above

Same as above

BLOOM: when 25% or more of the blossom buds are open

Same as above

Same as above

PETAL-FALL: when 90% or more of the petals have dropped

Same as above

Same as above

FIRST COVER: 7 days after Petal-Fall

Scab, Fabraea leaf spot, and fire blight

Same as above and scout for blighted leaves or twigs

SUMMER COVER SPRAYS: apply on a 10- to 14-day schedule until harvest depending upon the weather; refer to “days-to-harvest” interval on fungicide label

Scab, Fabraea leaf spot, and sooty blotch

Thiophanate methyl in combination with mancozeb or ferbam

Summary

Pears in the home orchard are commonly affected by several diseases every year. These are scab, Fabraea leaf spot, sooty blotch, and occasionally fire blight. The symptoms, causes, spread, and control strategies for these diseases of pear are discussed.

Pest & Disease Control for Pear Trees

Every fruit tree has the future potential for disease and insect damage. Factors such as location and weather will play a part in which issues your tree encounters. Disease-resistant trees are the best option for easy care; and for all trees, proper maintenance (such as watering, fertilizing, pruning, spraying, weeding, and fall cleanup) can help keep most insects and diseases at bay.

NOTE: This is part 6 in a series of 10 articles. For a complete background on how to grow pear trees, we recommend starting from the beginning.

Crown Gall

Trees appear stunted and slow growing; leaves may be reduced in size, little or no fruit. If tree is dead, inspect roots for hard, woody ‘tumors’. Note: many things can cause stunted trees.

Control

  • Consult County Extension Agent

Scale

Usually on bark of young twigs and branches, encrusted with small (1/16”) hard, circular, scaly raised bumps with yellow centers, may also be on fruit. Sap feeding weakens the tree.

Natural Control

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

Chemical Control

  • GardenTech® Sevin® Concentrate Bug Killer
  • Bayer Advanced™ Complete Insect Killer

Tarnished Plant Bug

Yellow-brown winged insect may have black spot or red stripes. Injects toxins into the buds and shoots causing ‘dwarfed’ shoots and sunken areas (cat facing) on fruit.

Natural Control

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

Chemical Control

  • Bayer Advanced™ Complete Insect Killer

Leafroller

Pale yellow or ‘dirty’ green worms. Leaves are rolled and webbed together where insects feed. Eventually becomes ‘skeletonized’.

Natural Control

  • Bonide® All Seasons® Horticultural & Dormant Spray Oil
  • Bonide® Captain Jack’s™ Deadbug Brew
  • Bonide® Thuricide® Bacillus Thuringiensis (BT)

Chemical Control

  • GardenTech® Sevin® Concentrate Bug Killer
  • Bayer Advanced™ Complete Insect Killer

Scab

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

Natural Control

  • Bonide® Citrus, Fruit & Nut Orchard Spray
  • Serenade® Garden Disease Control
  • Bonide® Copper Fungicide Spray or Dust

Leaf Spots

Fabraea Leaf Spot

  • Most often occurs in areas with warm, wet, humid summers. Young leaves develop red to purple pinpoint spots on top or bottom. Spots enlarge, turn dark brown, may coalesce, and could drop. Usually worse on lower half of tree, fruit may also develop spots and crack.

Septoria Leaf Spot

  • Infection mainly on foliage and on the upper surface of the leaf. Spots are grayish-white with purplish margins, which are sharply defined at maturity. Centers have scattered black dots. Dead tissue may fall out giving a shot-hole appearance. When infection is serious, leaves fall in late summer.

Natural Control

  • Remove all infested leaves and debris and bury or burn them.
  • Serenade® Garden Disease Control

Pear Psylla

Adult is transparent, yellow-brown 1/8” jumping winged insect. Immature has no wings. Usually on underside of leaves and leaf stem. Sap feeding weakens the tree. Sticky residues become growth media for Sooty Mold.

Natural Control

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

Chemical Control

  • Bonide® Borer-Miner Killer
  • Bonide® Total Pest Control
  • Bayer Advanced™ Complete Insect Killer

Aphids

They are the size of a pinhead and vary in color depending on the species. Clusters on stems and under leaves, sucking plant juices. Leaves then curl, thicken, yellow and die. Produce large amounts of a liquid waste called “honeydew”. Aphid sticky residue becomes a growth media for sooty mold. Dormant Oil will kill eggs, use next dormant season, also during ½” green kills newly hatched except Rosy Apple aphid.

Natural Control

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

Chemical Control

  • Bonide® Borer-Miner Killer
  • GardenTech® Sevin® Concentrate Bug Killer
  • Bayer Advanced™ Complete Insect Killer

Green Fruitworm

Bluish-gray moth. Larvae are 1” long, usually green or brown with white spots and body stripes. Feeds on young leaves and young fruits. Disfigures the fruit.

Chemical Control

  • Bonide® Borer-Miner Killer
  • Bonide® Total Pest Control
  • Bayer Advanced™ Complete Insect Killer

Fireblight

Blossoms and fruit spurs withered; looks as if ‘scorched’ by fire, with dark brown or blackened leaves; tips of leaves curl under. Twigs and branches die. Cut back infested branches 4” below disease. Disinfect shears between cuts with 1 part bleach and 10-part water solution. Dispose of pruning. Fall cleanup is essential, including all mummified fruits and leaves hanging on the tree. The above steps need to be done exactly as stated.

Natural Control

  • Serenade® Garden Disease Control
  • Prune out infected area.

Chemical Control

  • Ferti-lome® Fire Blight Spray (not on west coast)

Plum Curculio

Adult is brownish-gray 1/5” long, hard-shelled beetle with long snout and 4 humps on back. Cuts a crescent shaped hole under fruit skins and lays eggs. Worms hatch and tunnel into fruit. Premature dropping of fruit can occur.

Chemical Control

  • Bayer Advanced™ Complete Insect Killer

Tent Caterpillar

Hairy caterpillars that enclose large areas in webbing and feed on enclosed leaves. Remove web with rake and burn. Caterpillars are pulled out with webs.

Natural Control

  • Bonide® Insecticidal Soap
  • Bonide® Citrus, Fruit & Nut Orchard Spray
  • Bonide® Thuricide® Bacillus Thuringiensis (BT)
  • Remove web with rake and burn.

Chemical Control

  • Bonide® Total Pest Control

Codling Moth

Adult is moth, gray with brown patches on wings. Worms about 1” long. Fruits have holes from side to core.

Natural Control

  • Bonide® Captain Jack’s™ Deadbug Brew
  • Traps

Chemical Control

  • Bonide® Borer-Miner Killer
  • Bonide® Total Pest Control
  • Bayer Advanced™ Complete Insect Killer

Mites

Pinpoint size, many different colors. Found on undersides of leaves. Sap feeding causes bronzing of leaves. Severe infestations have some silken webbing.

Natural Control

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

Chemical Control

  • GardenTech® Sevin® Concentrate Bug Killer
  • Bayer Advanced™ Complete Insect Killer

Black Rot, Frog Eye Leaf Spot

Leaf symptoms begin 1-3 weeks after petal fall as small purple flecks. These enlarge into lesions with purple margins and tan to brown centers, resembling ‘frog eyes’. When heavily infected, leaves may fall. Fruit infection can begin as soon as bud scales loose and appear on young fruit as red flecks that develop into purple pimples. These do not grow much until fruit begins to mature. Spots on mature fruit are irregular, black with red halo. As they enlarge a series of concentric rings form alternating from black to brown. Lesions stay firm and are not sunken. Fruit mummifies and stays attached to the tree. Rot in seed cavity or around core may be caused by early infections, but these usually fall within a month after petal fall with no surface symptoms. May be reddish-brown sunken cankers on limbs.

Natural Control

  • Serenade® Garden Disease Control

Japanese Beetle

Adult is a metallic green beetle. It skeletonizes leaves. Larvae are a grub, which feeds on turf roots. Check turf product labels for timing of control of grubs. This is more of a problem east of the Mississippi river.

Natural Control

  • Traps

Chemical Control

  • Bayer Advanced™ Complete Insect Killer

Leafhopper

Various colors and similar to aphids this small, active, slender-winged insects are usually found on the underside of leaves. Retard growth, leaves become whitened, stippled or mottled. Tips may wither and die. This insect carries virus of certain very harmful plant diseases.

Natural Control

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

Chemical Control

  • Bayer Advanced™ Complete Insect Killer

Rose Chafer

Beetle has ½” long, tan wings with reddish-brown edges. Long, thin hairy legs. Skeletonizes leaves and flowers. Present in large quantities in June and July. Worst on sandy sites near grassy areas.

Chemical Control

  • Bayer Advanced™ Complete Insect Killer

Gypsy Moth

Egg masses are about 1” long, hairy and buff colored, found attached to buildings, walls, fences and trees. Caterpillars hatch out in April and feed on fruit and forest trees (including conifers). Cocoons are formed in late July and the moth emerges about a month later. Males are dark brown, less than an inch long. Females are buff-colored and heavy.

Natural Control

  • Bonide® Thuricide® Bacillus Thuringiensis (BT)

Thrips

Tiny, slender, fringed wing insects ranging from 1/25 to 1/8” long. Nymphs are pale yellow and highly active and adults are usually black or yellow-brown, but may have red, black or white markings. Feed on large variety of plants by puncturing them and sucking up the contents.

Natural Control

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

Leaf and Stem Blight

Leaves are soft and water soaked. Brown and black irregular blotches appear and spread to cover the leaves. Areas on the stems turn black, soft and sunken.

Natural Control

  • Bonide® Copper Fungicide Spray or Dust
  • Serenade® Garden Disease Control

In This Series

  • Introduction

Getting Started

  • Location
  • Planting
  • Soil Preparation

Care & Maintenance

  • Fertilizing
  • Pest & Disease Control
  • Pruning
  • Spraying
  • Watering

Other Topics

  • Harvesting

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