Weeping cherry tree diseases

Contents

Pest & Disease Control for Cherry Trees

As it grows, a cherry tree may experience issues caused by pests or diseases. Factors such as location, weather, and upkeep play a part in which issues your cherry tree encounters and how well it stands up against them. Disease-resistant cherry trees are easy-care options for growers who prefer a low-spray or no-spray orchard, and – for all cherry trees – routine maintenance* can help keep most problems at bay.

*Examples of good practices are: adequate watering, fertilizing only as needed, seasonal pruning, preventative and active spraying, fall cleanup and winter protection.

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

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

Cherry 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.

Control: Spray

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

Control: Natural 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

Cherry Fruit Fly

Adults are similar in appearance to a housefly, but smaller. Larvae are yellowish-white grubs. Traps are an option for luring adults.

Symptoms: Small, pinpoint-sting marks visible on fruit surface. Eggs are laid under fruit skin. Hatched larvae tunnel, making railroad-like mining pattern.

Control: Spray

  • Bonide® Fruit Tree Spray

Control: Natural Spray

  • Bonide® Captain Jack’s™ Deadbug Brew Garden Dust
  • Bonide® Citrus, Fruit & Nut Orchard Spray

Moths

Includes: Orange Tortrix, Oriental Fruit Moth, Codling Moth, Winter Moth, Western Tussock Moth, Cherry Scallop Shell Moth, etc.

Adults are moths that vary in size and appearance. 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.

Control: Spray

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

Control: Natural Spray

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

Borers

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

Adults are small brown beetles that may target the graft location (in young cherry trees) for laying eggs as well as damaged or sunken areas. Grubs have horseshoe-shaped heads and cream-colored bodies. Difficult to control once infested. Preventative spraying (including the ground around the roots) is a strong defense. Traps – in the form of tanglefoot-coated logs or posts that are later removed from the site and burned – are an option for luring adults.

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.

Control: Manual

  • 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)

Control: Spray

  • GardenTech® Sevin® Concentrate Bug Killer

Additional Resources

  • Contact local county Cooperative Extension for further advice

Japanese Beetle

Adult is a metallic-green beetle, which skeletonizes leaves. Larvae are cream-colored grubs that feed on turf roots prior to maturity. Turf pest-control may help reduce grub populations; check turf product labels for timing and control of grubs. Traps are an option for luring adult beetles.

Symptoms: Adults are often seen in groups – large infestations can cause stunted growth and stress by skeletonizing a majority of the leaves.

Control: Manual

  • If infestation is minimal, knock Japanese beetles into a jar of soapy water solution (they will become immobile when frightened as a defense mechanism)

Control: Spray

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

Control: Natural Spray

  • Bonide® Captain Jack’s™ Deadbug Brew Garden Dust

Leafhopper

Small, active, slender-winged insect appearing in various colors. Usually found on undersides of leaves.

Symptoms: Slows new growth; leaves become whitened, stippled, or mottled. Leaf tips may wither and die. Prone to carrying diseases to and from plants and trees; damaged caused by leafhoppers may be greater than the feeding done directly by the insect.

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

Control: Spray

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

Control: Natural Spray

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

Mites

Pinpoint-sized arthropods, appearing in many different colors depending on the type. Often found on undersides of leaves.

Symptoms: Sap feeding causes a bronze appearance in leaves. Severe infestations exhibit some silken webbing. Droughts or dry spells are advantageous for mite infestations.

Control: Spray

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

Control: Natural Spray

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

Scale

Usually on bark of young twigs and branches, encrusted with small (1/16-inch) hard, circular, scaly raised bumps with yellow centers. May also be on fruit.

Symptoms: Sap feeding weakens the tree.

Control: Spray

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

Control: Natural Spray

  • Bonide® All Seasons® Horticultural & Dormant Spray Oil
  • Bonide® Citrus, Fruit & Nut Orchard Spray
  • Bonide® Insecticidal Soap
  • Bonide® Neem Oil
  • Monterey Fruit Tree Spray Plus
  • Monterey Horticultural 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 (or “cat facing”) on fruit.

Control: Spray

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

Control: Natural Spray

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

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.

Control: Manual

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

Control: Spray

  • Bonide® Fruit Tree Spray

Control: Natural Spray

  • Bonide® All Seasons® Horticultural & Dormant Spray Oil
  • Bonide® Insecticidal Soap
  • Bonide® Thuricide® BT
  • Monterey Fruit Tree Spray Plus

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).

Control: Spray

  • GardenTech® Sevin® Bug Killer

Control: Natural Spray

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

Cherry Tree Diseases

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.

Control: Manual
Exposing an infected crown and upper root area of a cherry 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.

Botrytis Rot

Damage commonly occurs to stone fruit and their blossoms during a wet, cool season. It appears on ripening fruit as brown spots and becomes covered with light brown spores.

Symptoms: Appears similar to brown rot (below). Fungus will overwinter in the soil and in plant debris.

Control: Spray

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

Control: Natural Spray

  • Bonide® All Seasons® Horticultural & Dormant Spray Oil
  • Bonide® Neem Oil
  • Serenade® Garden Disease Control
  • Monterey Fruit Tree Spray Plus
  • Monterey Horticultural Oil

Brown Rot

Includes: mummy rot and twig and blossom blight

Brown rot is a fungal disease that commonly affects stone-fruit trees, including cherry trees, especially after a long, warm, wet spring. It is one of the most common cherry-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 turn brown and wither, but stay on the tree. Small sunken spots may appear at the base of infected blossoms, in the twig itself. Gummy brown “sap” may seep from these sunken areas. Leaves at the twig ends appear shriveled. Furry gray or beige mold forms on affected blossoms or twigs. The fungus rapidly spreads to the fruit.

Control: Manual
Plant a resistant variety, like Stark® Gold™ Sweet Cherry 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.

Control: Spray

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

Control: Natural Spray

  • Bonide® Citrus, Fruit & Nut Orchard Spray
  • Bonide® Copper Fungicide

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

Buckskin (X-disease)

Buckskin disease is spread by some leafhopper species and is managed by planting disease-free stock, controlling weeds that host leafhoppers and removing leafhopper vectors and all diseased trees.

Symptoms: Diseased trees produce leathery, bumpy fruit that is pale in color, even at harvest-time. On Mahaleb rootstocks, trees rarely have fruit issues, but will suddenly droop above the graft union. Buckskin disease (also called “X-disease”) is caused by a phytoplasma organism in the cells of infected trees. Trees are usually infected in summer and fall, but will not show symptoms until the following year.

Control: Manual
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.

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.

Control: Manual

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.

Control: Spray

  • Bonide® Fung-onil™ Multi-Purpose Fungicide

Control: Natural Spray

  • Bonide® Copper Fungicide
  • Bonide® Thuricide® BT
  • Monterey Horticultural Oil

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.

Control: Prevention

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

Additional Resources

  • Contact local county Cooperative Extension agent for further advice

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.

Control: Manual
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.

Control: Spray

  • Bonide® Fung-onil™ Multi-Purpose 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.

Control: Spray

  • Bonide® Fung-onil™ Multi-Purpose Fungicide

Control: Natural Spray

  • Bonide® All Seasons® Horticultural & Dormant Spray Oil
  • Bonide® Citrus, Fruit & Nut Orchard Spray
  • Bonide® Copper Fungicide Spray or Dust
  • Bonide® Neem Oil
  • Serenade® Garden Disease Control
  • Monterey Fruit Tree Spray Plus
  • Monterey Horticultural Oil

Other Cherry Tree Issues

No Blossoms or Fruit

Sweet cherry trees take about 4 to 7 years after planting (on average) before they bloom or bear fruit. Pie/Sour/Tart cherry trees bear a little sooner, within 3 to 5 years after planting. If enough time has been allowed to pass, and the cherry tree is otherwise healthy, there are a few things to do to help it become fruitful.

  • Make sure a pollinator variety is present. Most cherry trees require another different variety of cherry tree to be fruitful. Note: Sweet cherry trees and Pie/Sour/Tart cherry trees are not reliable pollinator for one another.
  • Make sure your cherry tree variety is recommended for your zone. Low winter temperatures can injure sensitive fruit buds and blossoms, 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 cherry 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.

Additional Resources:

  • Solving Fruit Tree Blooming & Bearing Problems

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).

Additional Resources:

  • Winter Protection for Fruit Trees
  • Drought Issues & How to Protect Your Trees

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.

Additional Resources:

  • Plan Ahead for Rainy Weather

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 cherry 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.

Control: Manual

  • 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.

In This Series

  • Introduction

Getting Started

  • Acclimate
  • Location
  • Planting
  • Soil Preparation

Care & Maintenance

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

Other Topics

  • Harvesting

Reasons For Cherry Leaf Spots: Treating Cherry Leaves With Spots

Cherry leaf spot is usually considered a disease of low concern; however, in severe cases it can cause defoliation and failure of fruit to develop. It primarily occurs on tart cherry crops. Cherry leaves with spots are the first symptoms, especially on new leaves. The spots on cherry leaves are easy to confuse with several other fungal diseases. Knowing what the signs are and implementing early treatment can help save your crop.

Recognizing Cherry Leaf Spot Disease

Cherry season is a cheery time of year with pies and preserves the result of a good harvest. Leaf spots on cherry can signify a disease that could compromise that yield. What causes cherry leaf spots? Most commonly a fungus called Blumeriella jaapii, once known as Coccomyces hiemali. It is prevalent in periods of intense rainfall.

The disease first appears on upper parts of leaves. The spots on cherry leaves will measure 1/8 to 1/4 inch (.318 to .64 cm.) in diameter. These fungal leaf spots on cherry trees are circular and start as red to purple in tone. As the disease develops, the spots become rusty brown to totally brown and begin to appear on the undersides of the leaves.

Whitish downy material appears in the centers of the spots, which is the spore of the fungus. The spores may drop out, making tiny shot holes in the leaves.

The causal fungi overwinter on infected dropped leaves. In the warming temperatures of spring with accompanying rainfall, the fungi start to grow and produce spores. These are transmitted through rain splash and wind to land on uninfected foliage.

Temperatures that enhance spore formation are between 58 and 73 degrees Fahrenheit (14 to 23 C.). The disease attacks the stomata of a leaf, which is not open until young leaves unfurl. Then spots can appear within 10 to 15 days after the leaf has become infected. The period between May and June is when the disease is most active.

Cherry Leaf Spot Treatment

Once you have cherry leaves with spots, the best control is to set up preventive measures for the next season. Fungicides are not very affective once the tree is in full leaf and much of the foliage is infected.

Begin removing and destroying the dropped leaves at the understory. These contain spores that will overwinter and infect the next season’s new leaves. In orchard situations, the best option may be to mow the dropped leaves to chop them up and hasten composting.

The following year, very early in the season just as leaves are beginning to bud, apply fungicide such as chlorothalonil. Apply this cherry leaf spot treatment as the leaves are beginning to unfurl and again two weeks after bloom to prevent disease development and save your crop of glossy, juicy cherries.

Cherry leaf spot

How to manage cherry leaf spot

If cherries are losing their leaves due to leaf spot, aggressive measures should be taken to control the disease.

Keep your orchard clean

  • Sanitation is a critical component of cherry leaf spot control.
  • Rake up and compost fallen cherry leaves in September or October.
  • The fungus survives the winter in fallen leaves. Removing these leaves will reduce disease spores the next spring.

Fungicides

If your trees have dropped the majority of their leaves before September, for several years in a row, fungicides can be used to protect leaves.

  • Fungicide applications should be started two weeks after bloom when leaves are completely unfolded. Applications should be repeated throughout the growing season at the interval listed on the fungicide label, including one application after harvest.
  • Fungicides with an active ingredient of myclobutanil or captan will protect leaves from infection with cherry leaf spot when applied properly.
    • The leaf spot fungi may develop resistance to myclobutanil if this fungicide is applied too often.
    • To avoid fungicide resistance, alternate between myclobutanil and captan when making repeated fungicide applications.
  • Fungicides with an active ingredient of copper may provide some protection against leaf spot infection.
    • Some copper fungicides are acceptable for organic production.
  • Fungicides work best if combined with sanitation.

Use Fungicides Safely

The name of the plant being treated MUST BE LISTED on the fungicide label or the product cannot be used! Some products are registered for use on ornamental Prunus species but are not safe to use on stone fruit that will be eaten. Always completely read and follow all instructions on the fungicide label.

Post harvest interval is important

Take care to wait the complete ‘post harvest interval’ (PHI) listed on the label. The PHI is the number of days you must wait after applying a fungicide before harvest is allowed. This time period allows fungicide residue to break down to a safe level.

Cherry (Prunus spp.)-Leaf Spot

Cause Blumeriella jaapii (formerly Coccomyces hiemalis), a fungus.

The disease is particularly severe on sour cherries, but also attacks sweet cherries in western Oregon and Washington. It has been found infrequently in arid areas east of the Cascade Range. It is especially a problem in newly planted orchards that are not being managed for brown rot. Resulting losses of fruit yield and quality are associated with a weakening of the tree as a result of early summer defoliation. Early defoliation delays flower bud acclimation to low temperatures in winter, which results in decreased flower bloom and fruit set for 2 years.

The fungus overwinters on fallen infected cherry leaves and in spring produces large numbers of spores. Air currents and rain move spores to healthy leaves. In spring, with moisture, they initiate new infections on young leaves through stomata. Once unfolded, leaves are susceptible throughout the growing season, but susceptibility decreases with age.

New lesions produce more spores, which can infect healthy foliage each time it rains in the spring. Fewer infection cycles occur in the PNW compared to Midwestern production areas such as Michigan. Other hosts include apricot, bitter and choke cherry and plum.

Symptoms On sour cherry leaves, variously colored spots develop on the upper surface. The spot or lesion rapidly enlarges, becoming brown or purple, and dies from the center outward. Infected spots are irregular or round and occur over the entire leaf surface. Individual spots never become large. They merge together to kill large areas of the leaf. Spot development precedes yellowing and leaf dropping. The area adjacent to the spot may remain green while the rest of the leaf turns yellow (the “green island” effect). Diseased leaf tissue may separate from healthy tissue, drop out, and give the leaf a shothole appearance.

On sweet cherry leaves, spots often are larger and nearly circular. Cream-colored fungal spore masses appear on the lower leaf surface associated with the spots on both sweet and sour cherries. On fruit stems, infections sometimes girdle the stem to cause a fruit drop. While infections occur on the fruit, they are less common than on foliage.

Cultural control

  • Rake up and destroy infected leaves. Leaves may be composted if completely decayed before spring.
  • Make use of any practice that encourages decomposition of leaves prior to spring bud break, such as mowing or flailing.
  • Apply urea to leaves after leaf fall in autumn to enhance decomposition of fallen leaves.

Chemical control Apply a fungicide at petal fall, shuck fall, and 2 weeks later. Postharvest applications are helpful in wet years. Rotate or tank-mix materials from different groups with different modes of action to prevent resistant strains from developing. Limit applications from any particular group to two (2) or fewer per year. Fungi resistant to Group 3 fungicides have been detected in Michigan. A forecasting program is available from Michigan to help time applications. Tests in western Oregon show the program is useful at higher temperatures.

  • Bonide Captan 50 WP may be used in Oregon home gardens at 1 to 1.5 Tbsp/gal water. H
  • Bravo Weather Stik at 3 to 4.1 pints/A. Do not apply after shuck split but may be used after harvest. Generally excellent control. Group M5 fungicide. 12-hr reentry.
  • Captan 80 WDG at 1.9 to 2.5 lb/A. Applications may be made day of harvest. Generally good control. Group M4 fungicide. 24-hr reentry.
  • CaptEvate 68 WDG at 3.75 lb/A. Can be used day of harvest. Group 17 + M4 fungicide. 24-hr reentry.
  • Cueva at 0.5 to 1 gal/100 gal water/A. May be used on day of harvest. Group M1 fungicide. 4-hr reentry. O
  • Eagle 20 EW at 2 to 3 fl oz/100 gal water for home orchards or landscape use. Can be applied up to the day of harvest. Group 3 fungicide. 24-hr reentry.
  • Echo 720 at 3.1 to 4.1 pints/A. Do not apply after shuck split. Group M5 fungicide. 12-hr reentry.
  • Gem 500 SC at 1.9 to 3.8 oz/A. Do not apply within 1 day of harvest. ‘Concord’ grapes may be injured if accidentally sprayed. Group 11 fungicide. 12-hr reentry.
  • Indar 2F at 6 fl oz/A plus a wetting agent. Generally good control. Group 3 fungicide. 12-hr reentry.
  • Luna Sensation at 5 to 7.6 fl oz/A. Do not use within 1 day of harvest. Do not use if already used for brown rot. Group 7 + 11 fungicide. 12-hr reentry.
  • Merivon at 4 to 6.7 fl oz/A. Do not use with EC or oil-based products. Only nonionic surfactants can be used within 14 days of harvest. May be used day of harvest. Do not use if already used for brown rot. Group 7 + 11 fungicide. 12-hr reentry.
  • Ortho MAX Garden Disease Control at 3.75 teaspoons/4 gal water. H
  • Pristine at 10.5 to 14.5 oz/A. Can be used day of harvest. Do not use if already used for brown rot. Group 7 + 11 fungicide. 12-hr reentry.
  • Procure 480 SC at 10 to 16 fl oz/A. Do not apply within 1 day of harvest. Group 3 fungicide. 12-hr reentry.
  • Propiconazole-based fungicides are registered. In the Willamette Valley, smaller, deeper green leaves have been measured on ‘Royal Ann’ cherry trees treated with a dilute application at 3 oz/A. Group 3 fungicides. 12-hr reentry.
    • Bumper 41.8 EC at 4 fl oz/A. May be used up to and including day of harvest.
    • Infuse Systemic Disease Control at 2 Tbsp/gal water. H
    • PropiMax EC at 4 fl oz/A. Do not use within 10 days of harvest.
    • Tilt at 4 fl oz/A. Do not mix with Syllit. May be used up to and including day of harvest.
  • Quash at 4 oz/A. Do not use within 14 days of harvest. Group 3 fungicide. 12-hr reentry.
  • QuiltXcel at 14 fl oz/A. May be applied the day of harvest. Sprayers should not be used on apples. Group 3 + 11 fungicide. 12-hr reentry.
  • Rally 40 WSP at 2.5 to 6 oz/A. Can be applied up to day of harvest. Has eradicant activity. Generally excellent control. Group 3 fungicide. 24-hr reentry.
  • Spectracide Immunox at 0.5 fl oz/gal water. Can be applied up to and including the day of harvest. Do not use more than seven (7) times per year. H
  • Sulfur 6L (52%) at 5 gal/A. May be phytotoxic if applied at temperatures above 85°F. Generally fair control. Group M2 fungicide. 24-hr reentry. O
  • Syllit FL at 1.5 to 3 pints/A plus another fungicide. Do not use within 7 days of harvest. Group U12 fungicide. 48-hr reentry.
  • Tebuconazole-based products. Can be applied up to and including day of harvest. Generally good to excellent control. Group 3 fungicides.
    • Orius 20 AQ at 8.6 to 17.2 oz/A. 12-hr reentry.
    • Tebucon 45 DF at 4 to 8 oz/A. 5-day reentry.
    • Unicorn DF at 2 to 3 lb/A. Includes sulfur in the formulation. 5-day reentry.
  • Topguard at 14 fl oz/A. Do not use within 7 days of harvest. Sprayers should not be used on apples. Group 3 fungicide. 12-hr reentry.
  • Topguard EQ at 6 to 8 fl oz/A. Do not use with silicone surfactants or within 7 days of harvest. Sprayers should not be used on apples. Group 3 + 11 fungicide. 12-hr reentry.
  • Topsin 4.5 FL at 22.5 to 30 fl oz/A. Do not apply within 1 day of harvest. This material may kill earthworms, which help decompose infected leaves. Group 1 fungicide. 2-day reentry.
  • Trionic 4 SC at 10 to 16 fl oz/A. Do not apply within 1 day of harvest. Group 3 fungicide. 12-hr reentry.
  • Ziram 76 DF at 5 to 6 lb/A. Do not use within 30 days of harvest. Generally fair control. Group M3 fungicide. 48-hr reentry.

Note Although effective, copper products are not recommended due to phytotoxicity to fruit.

Some registered products offer only suppression of this disease and thus are not recommended for use. These products include Fontelis.

Biological control

  • Serenade ASO (Bacillus subtilis strain QST 713) at 2 to 4 quarts/A. Active ingredient is a small protein. Unknown efficacy in the PNW. 4-hr reentry. O

Cherry leaf spot

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Maryland Grows

Q: I have a cherry tree that has been in the ground for three years and has grown well. This year, the leaves have holes and they are falling to the ground already. The tree was sprayed twice with an insecticide and a fungicide. All sprays have been at the recommended dilutions. The leaves continue to fall. What is the problem?

A: The foliage of your tree looks like it was subject to cherry shot hole disease. Infected leaves will turn yellow and drop from the trees in mid-summer, if the infection is severe. This disease can be common when we have wet spring weather. The pathogen may continue to infect leaves throughout the growing season if rainy weather persists. In most cases, trees recover from this disease and no treatment is necessary. Rake and dispose of fallen leaves in the fall to reduce overwintering pathogens.

In addition, be sure to identify a pest or disease before you decide to spray. Some insecticides are “broad-spectrum” products which will also harm many beneficial insects. Also, an insecticide will not do anything to treat a fungal or bacterial disease.

Learn more about cherry shot hole on flowering cherries and how to manage it.

Have a plant or pest question? University of Maryland Extension’s experts have answers! Send your questions and photos to Ask an Expert.

PESTS AND DISEASES OF CHERRY TREES

Article by David Marks

Cherry trees are well known for suffering from a range of pests and diseases in the UK. Treatment has been made much easier in recent years with the introduction of dwarfing and semi-dwarfing rootstocks.

Bird damage can now be much more easily controlled because the trees can be kept to a manageable size. The same applies to diseases such as canker – affected branches are within reach and can be quickly treated.

SILVER LEAF OF CHERRY TREE

The following are symptoms of a Silver Leaf fungal infection:

  • A silver sheen to the leaves. This typically does not affect the whole tree, it affects only branches which are suffering from the disease.
  • Cut through a suspect branch which is 3cm or more wide and you will see a brown stain in the centre. wet the cut if this is not immediately visible. This is the defining symptom of Silver Leaf in cherry trees.
  • Affected branches will die back.

An example of the silver sheen to the leaves is shown below:

The confirming sign of Silver Leaf infection is shown below, where a branch has been sawn through to reveal the tell tale brown stain:

For more identifying features of Silver Leaf and how best to treat it, visit our page dedicated to this disease of cherry trees.

BROWN LEAVES – CHERRY LEAF SCORCH / SPOT

When most of the leaves on your cherry tree turn brown before autumn, your tree almost certainly has a fungal infection. The two most common are cherry leaf scorch and cherry leaf spot.

The symptoms differ slightly but the treatment remains the same. Click here for our page devoted to fungal problem.

BIRDS AND CHERRY TREES

Birds can be a real problem with cherry trees and pigeons are the main culprit. There are many suggestions on the internet and in gardening books for deterring them but, take our word for it, only one works. You need to net the fruit tree, or at least individual branches, if birds are a problem in your area.

Both fruit and younger leaves can be affected. We first describe fruit damage then briefly describe leaf damage.

In extreme cases you may not even notice the birds, the only sign of a problem being no fruit or damaged leaves. The birds eat the under-ripe so quickly that some gardeners don’t realise that birds are doing the damage. Look for signs of cherry stones in the surrounding area. Birds drop the stones after they have eaten the cherry flesh.

Pigeons and other birds have an annoying habit of pecking at the fruit just before it’s ripe and it’s no use trying to beat them to it. Under-ripe cherries will not ripen when picked from the tree.

Pigeons and other birds can be a major problem

If your tree is on a dwarfing or semi-dwarfing rootstock such as Gisela 5 or Colt then this will not be too much of a problem. However, if you have a full sized cherry tree (which can easily be higher than a two-storey house) then you have a different problem altogether. Our advice, in that case, would be to buy a new cherry tree on an appropriate rootstock.

Not only do we recommend netting as the only solution, but so do all the professional growers. Decoys, hanging CDs, silver foil and other solutions just don’t frighten pigeons for long enough.

Leaf damage to a cherry tree

Leaf damage (see above picture) which primarily affects younger tender leaves is almost always caused by birds, and pigeons are the prime culprit. The damaged leaves will have jagged edges where the birds have torn away the leaf flesh with their beaks. Very frequently, you will never see the birds which have caused the damage.

A cherry tree can be productive for many decades so it makes economical sense to buy netting which can reliably prevent birds and which will last for many years.

Your own personal experience will dictate when the best time is to cover with netting. We would suggest that initially you try early June if they are eating the fruit. If you find that the birds attack the developing fruit before that then note the time that the damage first starts for a guide the next year. With leaf damage the netting needs to applied by mid April.

LEAF MINERS

The visible symptoms are squiggly lines which appear on the upper side of the leaves. The lines can be a variety of colours, white or deep brown being the most common (see the picture below). The pest which is causing the damage on cherry trees is Lyonetia clerkella often called the Apple Leaf Mining Moth. They normally have three generations per year.

Picture courtesy of Jenny L

There are no pesticides available to UK gardeners for the Apple Leaf Mining moth. However, although unsightly, they will not affect the health of an established cherry tree.

There are two steps you can take to reduce the damage. The first is to pick off and burn badly affected leaves. The second is to pick up all fallen leaves and burn them as well. The pupae overwinter in the bark of the tree or on the ground. Clearing the surrounding soil (and gently hoeing it) of any debris will also help.

BACTERIAL CANKER

The following are symptoms of Bacterial Canker on cherry trees:

  • Branches and stems have sunken and malformed areas on them. The size of the affected area can be as small as a two penny coin but can also spread over very large areas of the branches.
  • Damaged areas will often have a dark gum oozing from them which may harden to become almost solid after time.
  • Leaves turn prematurely yellow but do not shrivel. They drop off sooner than normal.
  • There may be small brown marks on the leaves which fall out leaving the leaves with small holes in them, this often referred to as shot hole.

Young cherry trees are more likely to be affected compared to established trees. There are no chemicals or treatments available to the amateur gardener (Bordeaux mixture and similar copper based treatments are no longer sold in the UK) for Bacterial Canker.

Your only option is early detection and removal of infected wood. Click here for our page dedicated to the identification and treatment of Bacterial Canker.

SPLITTING OF CHERRIES

One of the commonest problems with cherry trees is the fruit splitting. This is not a pest or disease, it is a condition that some cherry trees suffer from. Variable weather can affect the likelihood of this happening.

Picture courtesy of Yara

Different varieties of cherries are more or less likely to fruit splitting. For instance, Sweetheart, Sunburst, Summer Sun, Penny and Morello are relatively resistant to fruit splitting and cracking whereas Skeena and Napoleon are likely to have a good proportion of the fruit split.

Aside from choosing a resistant variety there is very little that you can do to prevent fruit splitting. Excessive nitrogen contributes to thin cherry skins so avoid this type of fertiliser. Some gardeners believe that overwatering causes splitting but in fact the evidence does not support this.

Cherry fruits absorb the majority of their liquid from the fruits surface so it is humid conditions and water on the skin surface which can contribute to skin splitting rather than excessive water at the roots (see this article here). If you can protect your cherries from the worst of the rain then that will help greatly but it’s very difficult to do.

SMALL BLACK LEECHES / SLUGS ON LEAVES

This is the Cherry Slug Sawfly (Caliroa cerasi) sometimes also called the Pear Slug Sawfly. It affects pear, cherry and apple trees as well as some ornamental shrubs, hawthorns in particular. On fruit trees, the black leech like creatures are in fact green but covered with black slime. The slime is a protection mechanism to avoid being eaten by birds.

Picture courtesy of reader Anthony T
Cherry Slug Sawfly (click to enlarge)

The lifecycle of the Cherry Slug Sawfly starts with the pupae overwintering in the soil beneath the tree. In spring the actual sawflies emerge and lay eggs on the leaves. The eggs then hatch into the leech like creatures.

It is this slug / leech like stage which does the damage. They feed on the upper surfaces of the leaves with their black slime making them very unattractive to birds. The picture above shows the leaf damage very clearly, it is almost always restricted to the top surface of the leaf.

The larvae feed for three to four weeks and then fall off onto the ground. They will then hatch into a second generation within the same year and it is this second generation which does the significant damage. This normally occurs in late August to mid September.

In severe cases they can damage a huge amount of leaves. They are rarely fatal to the tree and fruit production is normally unaffected because the damage occurs so late in the year. They do make the leaves very unsightly however and can cause problems for already weak trees.

Removing them by hand and disposing of them is one solution but the size of many fruit trees makes this a difficult task. They can be knocked off with a strong jet of water. Spraying with a contact insecticide such as Bifenthrin was the most common treatment but in the UK this insecticide is no longer permitted for amateur gardeners.

Scotts Bug Clear is the recommended alternative but there is little hard evidence for how effective it is with the Cherry Slug Sawfly.

LEAVES CURLING

This normally a sign of aphids such as blackfly and greenfly. The most common is the Cherry Blackfly. They attack the leaves causing them to curl upwards and inwards which protects the aphids from predators such as birds. They are attracted to young shoots in particular which may end up as a distorted mass.

Often gardeners cannot see the aphids with the naked eye and it is necessary to use a magnifying glass. Another sign of aphids is the presence of ants on the leaves or stems of the tree. They farm the aphids and only make matters worse. The earlier you treat aphids the better your chances are of a good crop of cherries.

Adult cherry Blackfly

We have a page dedicated to identifying and treating (organic and chemical methods) aphids which can be found here.

CHERRY FRUITS DROP BEFORE RIPENING

If the tree is otherwise healthy, fruits dropping off has two main causes. Where 30% or less fruit drop this is quite natural. Cherry trees often over-produce fruit and they have a natural mechanism which causes some of the fruit to fall off before ripening. This allows the tree to concentrate its energies into producing a slightly smaller amount of healthy fruit.

Where more than 30% of the fruits fall off before ripening this is sometimes called “cherry tree run off”. The exact causes are not known but it is believed to be adverse weather conditions earlier in the season, frequently at blossom time. Currently there is no cure for this. The overall health of the tree is not affected and it should resume normal fruit production in later years.

Research is ongoing to find out more about Cherry Fruit Drop an the article found here may be of use. It would suggest that where the problem occurs over several years a solution might be to reduce the number of fruits (as early as possible) to about 2 per fruiting spur. Normally there are six to eight fruits per spur.

BLACK CHERRY APHIDS

The first signs of Black Cherry Aphids will be in spring when leaf buds begin to open. The aphids have a black, shiny surface to them and are about a quarter of a centimetre long. They are clearly visible to the naked eye and will multiply rapidly.

They cause the leaves to curl in on themselves making treatment very difficult. In many cases a cherry tree will not be badly affected as far as cropping is concerned although younger trees may be damaged. The aphids will suddenly disappear in July, looking for more suitable food, however the distorted leaves will remain.

They should be treated exactly as described for aphids here.

SPOTTED WING DROSOPHILA

The key identifier for Spotted Wing Drosophila is one or more pin prick sized holes in the skin. Later on the fruit will collapse in on itself.

Picture courtesy CDFA

This is a difficult pest to control so we have written a page specifically about how to identify it and treatments. .

Fungicide considerations for cherry leaf spot control at first cover

Cherry leaf spot is the most important fungal disease of tart cherries in Michigan. The leaf spot fungus Blumeriella jaapii infects leaves with symptoms first appearing on upper leaf surfaces as small purple spots. As spots accumulate on leaves, the leaves turn yellow and fall. The amount of lesions required causing leaf yellowing and drop is variable. Sweet cherries can tolerate quite a few lesions before leaf drop occurs; however, Montmorency tart cherries will drop with only a few lesions, signifying the importance of proper leaf spot management.

Ascospore discharge from the cherry leaf spot pathogen is highest over a wide temperature range (60 to 85 degrees Fahrenheit) and lowest at 41 to 46 F. Ascospores are usually discharged starting at petal fall and continuing for the next four to six weeks. The optimum conditions for lesion development are temperatures of 6 to 68 F with rainfall or fog. After lesions appear on upper leaf surfaces, examination of the underside of leaves reveals a proliferation of white spore masses. These spores are dispersed by rain and wind within trees and to adjacent trees; such secondary cycles can continue repeatedly under favorable conditions through autumn.

Prior to shuck split, the fungicide of choice for cherry leaf spot management is chlorothalonil because this is a broad-spectrum fungicide with excellent efficacy against cherry leaf spot. After shuck split, Bravo WeatherStik is the only chlorothalonil fungicide that can be used for cherry leaf spot, and must be used under conditions of the Section 24 (c) label.

The first cover spray timing after shuck split is a critical disease timing in tart cherry orchards. This is not only because warming temperatures favor cherry leaf spot spore discharge and infection, but also because other diseases such as powdery mildew become active (see the Michigan State University Extension article “Controlling powdery mildew in tart cherry orchards”). At first cover, fungicide applications need to target both cherry leaf spot and powdery mildew.

There are three currently-registered fungicides that effectively control both cherry leaf spot and powdery mildew. These are the new SDHI premixes Luna Sensation and Merivon and the strobilurin fungicide Gem. Luna Sensation and Merivon both provide excellent control of cherry leaf spot and powdery mildew. These new or second-generation SDHI premixes are replacements for Pristine. Pristine contains the older or first-generation SDHI compound boscalid, and we have detected resistance to boscalid in cherry leaf spot populations in northwest and west central Michigan orchards. Our field trial results show that both Luna Sensation and Merivon effectively control boscalid-resistant cherry leaf spot. For resistance management, these two practices are absolutely critical:

  1. Use Luna Sensation and Merivon at high-label rates! Suggested rates are 5.6 fl oz/A for Luna Sensation and 5.5-6.5 fl oz/A for Merivon.
  2. Both of these premixes should also be tank-mixed with Captan. A minimum rate of Captan 80 WDG to be included would be 1.75 to 2 lbs per acre.

Gem remains highly effective against both cherry leaf spot and powdery mildew. This fungicide is also prone to resistance development and we have observed this happen with apple scab. Because of the length of time in years we have been using Gem on tart cherry, this fungicide definitely should be tank-mixed with 2 lbs Captan 80 WDG per acre.

See also

  • Video: Evaluation of SDHIs for control of cherry leaf spot, powdery mildew, and American brown rot
  • Video: SDHI fungicide premixes: resistance management strategies for the SDHIs
  • Video: Identifying cherry leaf spot in tart cherry

Dr. Sundin’s work is funded in part by MSU’s AgBioResearch.

Cherry Leaf Spot

It is a challenge to identify problems from a photograph, but we suspect if this is on just a few leaves, it may be cultural – lack of too much water, weather conditions. Or your tree may have cherry leaf spot, caused by the fungus Blumeriella jaapii. Cherry leaf spot targets the foliage of cherry trees but can also infect stems and fruit. Small purple spots on the tops of leaves are generally the first symptom of this fungal disease. The spots turn brown and begin to enlarge and collapse, leaving a hole in the foliage. Older leaves will yellow and drop from the branches, and the cherry tree can lose all its leaves, which weakens the fruit tree and increases its susceptibility to cold damage. Be sure to clean up all of the fallen leaves and dispose of in your garbage. Suggest you take a few sample leaves to a horticulturist at your local garden center or public botanic garden (in a baggie) to see if the problem can be confirmed in hand as well as recommended controls, if needed.

Properly timed applications of fungicide will help prevent cherry leaf spot. Start fungicide preventive sprays at the petal fall stage and repeat every seven days until harvest. Some say way until the new leaves in the spring and others to start treatment now. It would be best to confirm that this is the problem and go from there. This happens a lot in humid weather places with often with overhead watering.

You may want to get a second opinion and take a sample to your local cooperative extension for confirmation. They will also be your best source for treatment of the problem.

The Various Problems That Weeping Cherry Trees Face

Other than bacterial and fungal infections, spider mites, and borers are some of the common weeping cherry tree problems. Here we provide information on various diseases and troubles associated with the tree, and also general guidelines about how to take care of the same.

Native to Japan, the weeping cherry trees are of moderate sizes. Their long drooping branches are like the weeping willow, that get covered in beautiful light pink or white blossoms in spring make them a sight to behold. Like other trees of the weeping form, weeping cherry trees provide a lot of shade under their drooping branches. Hence it is difficult to grow anything under the shade. These trees belong to the genus Prunus and grow between 20 and 40 feet tall. There are a number of varieties of this tree, the most common of which are the Shidare Yoshino, Hogan, and the snow fountain weeping cherry trees. Although these trees grow in soil with less nutrients, they are prone to a number of diseases that can mar the looks. Here are some problems that might crop up while you grow a tree of this sort, along with some tips on its proper care.

Viral and Bacterial Infections

Bacterial diseases like leaf spot and twig canker are some of the common problems you could come across. One may notice gum dripping from the canker, usually in spring and summer. The disease can be detected by the presence of black or brown spot and dull brown spots in place of the smooth bronze bark of the youngest branches. The cherry leafroll virus delays flowering in the tree and also spoils the fruits.

Fungal Infections

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Weeping cherry tree suffers from fungal infestations like the red spot that causes holes in the leaves or the powdery mildew that manifests as deposits of fine white powder on the leaves or white patches on the twigs of the tree. Leaves may drop before the fall season. Silvery leaf fungus makes the leaves appear silvery. Cherry leaf spot causes dark spots on the leaves and their early loss. It is common in humid regions. The leaves may turn yellow. Brown rot causes the fruit to rot and also affects the branches and flowers of the cherry tree. Fungus on a weeping cherry tree, if detected early, can be stopped from spreading to other parts.

Insects and Pests

When the weeping cherry tree gets enough amount of water and sunlight, it is usually free from pests or fungal infections. However, under drought like conditions, it becomes an easy prey for aphids, scales, spider mites and borers. Tent caterpillars are another pest of the weeping cherry trees that gardeners should keep a look out for. Japanese beetles feed on the newly emerged leaves of the tree, in early summer. The beetles attack trees in sunny locations. They gather on the higher branches and cause significant damage to the tree. The leaves turn brown and as the beetles eat them up, only a skeleton of veins is left behind. Black knot (dark growth on the tree), gray mold, verticillium wilt, and wood rot are some other common diseases that can destroy the health and beauty of weeping cherry trees.

Controlling Pests and Diseases

Organic Treatments

Ensuring appropriate moisture content in soil is the best way to keep the tree free of pests and fungal infections. Although pesticides can be used to tackle most of the pests, there is an easy, organic way of controlling common pests like spider mites, aphids and borers, and that is using insects like pirate bugs and lady beetles. Alternately, bacillus thuringiensis (BT) can be used to get rid of spider mites.

Insect Repellant

To tackle the problem of tent caterpillars, trim the parts that bear the nests. Garden borers can be kept off the weeping cherry tree bark by either spraying the bark or applying a coat of solution made by mixing half a pound of diatomaceous earth with a tablespoon of liquid soap.

Insecticides

An insecticide with pyrethroid protects the tree from Japanese beetles for 2-3 weeks. One that contains carbaryl helps protect the tree for 1-2 weeks while insecticides with neem or pyrethrin protect the cherry tree from beetles for 3-4 days only.

Pruning

Timely pruning helps avoid bacterial and fungal infections. Affected parts of the tree should be removed periodically. Pruned parts should be burned as it helps kill the spores and fungi. Regular use of fungicides, under the guidance of an expert, helps avoid fungal infections. Viral infection generally results in the death of the plant. A dead plant can spread the virus and so it should be removed and burned. This way, you can prevent spread of infection in the nearby plants. As a safety measure, you can always use virus-free planting material.

General Care

Watering

These trees can grow in almost any soil type, but they require plenty of water. Hence plant them close to some water source like a pond or lake. They prefer a well watered soil. However, ensure that the soil does not get water clogged. Weeping cherry trees are very sensitive to water content in the soil. Soil that is too wet can destroy the health of the roots. Hence, be sure that the soil is moist and well-drained for proper growth.

Sunlight Needs

Weeping cherry trees love sunlight. Also given the fact that these trees should get enough space for their branches to attain their full growth, plant these trees in large open spaces where they would get proper sunlight and enough place; so that the beauty of its flowers can be appreciated when they are in full blossom.

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Pruning and trimming is important to ensure that these trees grow properly. Although it is rare, in case a new leader branch comes out from the tree, trim it to prevent nutrients being directed to that branch. Trim the tips of the hanging branches just a few inches above the ground. While pruning or trimming the tree, be careful of not injuring any part of the tree as that would leave the bark open to fungal and bacterial infections.

Weeping cherry trees are wonderful consideration for landscaping. If you are planning to include this majestic tree in his landscape design, it is important for you to know the common problems associated with this tree, and take proper care accordingly. These trees become the pride of their owner as they stand in splendor with their blossoms in full bloom during the spring season.

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Weeping Cherry Tree Has Brown Leaves

June 7, 20190 found this helpful

Your tree is damaged by a very common disease called tree canker. Very often it is due to a fungus. This disease has to be treated very quickly and it could be a bit too late as your tree already shows a lot of damages and it is a disease easier to prevent than to treat. The damages that are symptoms of the disease to be watched, are the little bumps and the little splits on the trunk. You can still give your tree a chance with first a treatment with copper spray. Be very careful to do not overuse or overdose the copper spray. Copper spray is the best treatment against fungi but when overdosed it becomes dangerous for the environment (and the gardener too !). You can also try to dig out the little bumps you see on the trunks and treat the holes you make by doing so with tree wound painting or linseed oil. To prevent the disease, first get rid of all the little pieces of dead wood which are by your tree on the surface of your soil because they make a nice home for fungi. Every autumn “paint” the trunks of your fruit trees up to the base of their main branches, and the base of the main branches with a mix of lime. This is called to “whitewash”. It is very important to whitewash the trunks because in the winter or early spring there are days when the bare trunks of the trees are heated by sunlight when the ground is still cold or even frozen and the temperature drops at night. The trees which are dormant at that time can “wake up” and start their activity too early or the trunks can start splitting because of the brutal changes of temperature and it is through these splits that the bugs or fungi can get inside the trunks and start damaging them.

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You can find the receipt of this natural paint here: www.organicgardener.com.au/…/lime-based-whitewash
About cutting the damaged parts of the tree and letting it grow from its base, the problem is that your tree is in fact a grafted tree and the new shoot coming out of the ground is born from the rootstock and it will not necessarily be a weeping cherry tree. You could let it grow and then graft it with a branch of weeping cherry tree (if you want to learn how to graft trees of course). The first thing you need to do for the health of your tree is to protect the rootstock because it is too close to the ground and has been cut horizontally. On a tree, you should never leave a flat surface unprotected because water accumulates, enters the wood and makes it rot and it becomes a gateway for viruses, fungi and xylophagous insects. When you cut a part of a tree, you always have to cut it in bevel, so that the water slides and does not stagnate on the cut, then you must treat the cut with a waterproofing like linseed oil and of course you always sterilize the blades of the instruments you use with alcohol. If you buy a new cherry weeping tree, try not to buy a grafted tree, but if only grafted trees are available, look for a long rootstock that you will be able to plant with the grafted part well off the ground. Most of the time the rootstock top is covered with wax to protect it, it is a good point, but if you see that it is protected with wax AND cut in bevel, then you will know that it has been grafted by a good gardener. Reply Was this helpful?

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