Lilac diseases and pests pictures

Miss Kim Lilacs – Knowledgebase Question

Lilacs (Syringa)
Posted by stilldew
Lilacs can play host to leafminers (which tunnel around between the upper and lower leaf surfaces), and to bacterial leaf blight. Both of these problems will make leaf tips turn brown and curl up.
Leafminers are the larvae of an adult fly. She makes a little slit in the surface of a leaf and lays her eggs. The eggs hatch into little worms who happily feed on leaf tissue. Since they’re between the upper and lower leaf surfaces, they are immune to insecticide applications. When they’re mature enough they make an exit hole in the leaf and spin a thin web to lower themselves down to the ground. Here’s where they pupate, emerging the following spring.
Insecticides are not very effective against these pests. Your best course of action is to pick off any leaves with miner tunnels and squish them to kill the larvae.
Lilac leaf blight is a common problem, especially if plants are stressed. To avoid, maintain adequate spacing between plants, prune out and dispose of affected tissues as soon as you seed them, and don’t overfertilize.
The disease can overwinter, and can be resistant to copper based fungicides. Spray with Bordeaux (lime-sulfur) after leaf fall and again in the early spring. Be sure to rake and remove all fallen leaves from the garden.
Hope your Miss Kim regains her health!

How to recognize, treat and avoid lilac bacterial blight

CORVALLIS, Ore. – Do new buds and branches on your lilac look blackish, like they’ve been scorched by a blowtorch? Your bush might have a bacterial plant disease called lilac blight.

A cool, wet, rainy, spring season favors development of lilac blight, especially if rains follow a late frost or winter injury. Oregon State University Extension plant pathologists are warning that this might be a favorable year for the disease.

Actually known to plant pathologists by the complete name of “lilac bacterial blight,” this disease is caused by a bacterium Pseudomonas syringae pv. Syringae. The same organism is the source of bacterial blight on pear, blueberry, cherry, maple, and many other woody plants and the symptoms of lilac blight are similar in appearance to fire blight in fruit trees.

At first, leaves look perfectly healthy and then a short time later they look as though someone has placed an open flame near them. The dark black streaks on one side of young shoots show the progression of the disease. The flowers will wilt and turn brown and unopened flower buds become blackened.

Lilac blight is difficult to control and it is recommended that you buy blight-resistant varieties whenever you plant new lilacs.

It also helps to space and prune your lilac plants so they are not rubbing against each other and air can circulate freely between the plants. Do not fertilize late in the growing season. Do not over fertilize young plants because high nitrogen favors disease development, explained Melodie Putnam, OSU Extension plant pathologist.

If your lilac bush does have infection, prune and burn all infected parts as soon as you notice them. A spray of copper sulfate during the early spring each year should help prevent the problem before the buds begin to break.

Lilac blight bacteria over-winter on diseased twigs or on healthy wood. Factors that weaken or injure plants – wounds, frost damage, soil pH, poor or improper nutrition and infection by other pathogens – predispose them to the disease.

Sources of this disease can include old cankers, healthy buds, leaf surfaces and nearby weeds and grasses. Wind, rain, insects, tools and infected nursery stock spread the bacteria.

Some species of lilacs have shown resistance in western Washington including S. josikaea, S. Komarowii, S. microphylla, S. pekinensis, and S. reflexa. Most cultivars of S. vulgaris are susceptible, but some have been observed with less disease when planted in a garden; those include ‘Edith Cavell’, ‘Glory’, ‘Ludwig Spaeth’, and ‘Pink Elizabeth’. Note that ‘Ludwig Spaeth’ is highly susceptible under intense nursery production systems.

The disease starts as brown spots on stems and leaves of young shoots as they develop in early spring. A yellow halo may also be around the spot. Spots become black and grow rapidly, especially during rainy periods. Further infectious development depends on the age of the part of the plant attacked.

On young stems, infection spreads around the stem and girdles it so the shoot bends over at the lesion and the parts above it wither and die. Infections on mature wood occur only on cherry trees, not on lilacs.

Young, infected leaves blacken rapidly starting near the margin and continuing in a wedge-shaped pattern down to the petiole. Eventually the entire leaf dies. On older leaves, spots enlarge slowly. Sometimes, several spots will run together, and the leaf may crinkle at the edge or along the mid-vein. Flower clusters also may be infected and rapidly blighted and blackened. Buds may fail to open or may turn black and die shortly after opening. Symptoms are similar to those of winter injury.

To see photos of this disease, visit OSU Extension’s PNW Plant Disease Management Handbook.

New lilacs that will fresh up your yard and home

The problem with Miss Kim is she doesn’t look like what you might expect. She’s a lilac (Syringa patula), but not what we usually think of as a lilac.

Miss Kim, who is from north China and Korea, is a different species from the lilac we know in the United States, called, appropriately, common lilac (S. vulgaris), and hailing from southern Europe. She looks and acts differently from, and is in many ways better than, her common lilac cousin.

A better fit for smaller spaces

For one thing, Miss Kim is a compact shrub, often billed as growing only 3 feet high and wide. In fact, she’s capable of growing 8 to 10 feet. That’s still substantially smaller than common lilacs, which, left to their own devices, swell to 20-foot behemoths. My own Miss Kim is 5 feet high, in her third year, and still growing strongly.

And rather than creating an arching fountain of stems, leaves, and flowers, Miss Kim presents a dense, rounded mass of greenery and flowers. Her leaves are also smaller than those of the common lilac and, with their rippling surfaces, lend an unlilac-like look to the shrub.

Miss Kim also looks decidedly unlilac-like in summer, when her leaves retain their healthy green color rather than being marred by the powdery mildew disease that attacks common lilac (but does those plants no particular harm). In autumn, as common lilac’s leaves drop with little fanfare, Miss Kim’s leaves turn reddish burgundy.

Flowers differ also

Face it: We grow lilacs mainly for their flowers. In this respect, Miss Kim is similar to her Occidental cousin. Her blooms, which open two weeks or more after those of the common lilac, have more white in them, giving them an icy appearance.

The flowers, like those of common lilac, are fragrant. Not to my nose deliciously so though because they have more of the aroma of privet (a lilac relative). For some reason, Miss Kim changes once she comes indoors, however, then becoming pleasantly and strongly fragrant, with even a single cluster of blossoms perfuming a whole room.

Other lilacs worth growing

Miss Kim is not the only lilac that is unlilac-like. There’s also the so-called early lilac (S. oblata) from Korea, which, besides blooming early, has loose panicles of flowers and nice autumn leaf color.

Japanese tree lilac (S. reticulata) is — what can I say? — from Japan and a tree, developing a hefty, single trunk and blooming a couple of weeks after common lilacs. The branches become smothered in frothy, white blooms.

Meyer lilac, from northern China, is unlilac-like in that its blooms develop all along the stems, covering the entire shrub from top to bottom.

Cutleaf lilac, from western China, is notable for having finely lobed leaves that give the whole bush a lacy texture.

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Please help….What are these dark spots on lilac leaves?

Gosh, you ARE having a rough time with lilacs, holleymc! You should be enjoying their scent instead!
There are hundreds and hundreds of leaf spot infectious agents out there. The spots can be caused by fungus, bacteria (like your Lilac Bacterial Blight), viruses and chemical injury.
Chemical injuries can happen when one uses insecticides or fungicides that a plant is sensitive to. Even if not applied close to the healthy plant, the vapors can still reach far away plants because of the wind. So consider if you have used any insecticides/fungicides recently. I cannot comment on Southern AG Copper Fungicide because it is not sold here but just review the back of the product to make sure that its use does not have warnings.
Observe which leaves are being infected. If the outer leaves are affected the most (leaves in contact with the sun for example) then minimize as much as possible watering of the leaves and water the soil instead. If that is not possible (say because the sprinkler always hits the lilacs when it goes off) then try to water very early in the day only and water when the soil is almost dry.
If it is fungal in nature, observe good sanitation techniques such as: pick up plant debris; replace mulch if the infestation is heavy; water only when the soil feels like it is drying up; dispose of affected leaves in the trash when they fall down; maintain good air flow between plants (do not overcrowd them); etc. Other fungal infestations are oportunistic; they take advantage of existing leaf injuries to infest the shrub.
Viruses usually spread when you prune an infected plant and then prune a healthy plant with the same pruners. Or when a healthy plant suffers an injury. Roses are notorious because their stems run against each other and the thorns break tissue at times. So dip pruner blades in a solution of water and bleach (1 part bleach, 9 parts water) to disinfect pruners if you intend to prune healthy and sick plants.
Because you already have a bacterial infection and now have another problem, I would send leaf samples to an Agriculture Extension Service or university for analysis. Clemson University’s Home & Garden Information Center would be my starting point if I lived in SC:
I would also keep a list of lilacs that resist Bacterial Blight handy. Just in case you get tired of the constant battle and prefer to switch to other varieties of lilacs… http://plantclinic.cornell.edu/FactShee … blight.htm

Lilac Leaves Turning Brown – Knowledgebase Question

It sounds to me like bacterial blight, a common problem in lilacs in your growing region. Bacterial blight of lilac is caused by the bacterium Pseudomonas syringae pv. syringae. The disease is also commonly referred to as Shoot Blight and Blossom Blight. The pathogen is capable of causing damage to all types of lilacs including Japanese, Chinese, Persian and common varieties. Some researchers suggest that white flowering varieties may be more susceptible to infection than other varieties. The disease is usually associated with plants that have been stressed by drought conditions, improper fertilization, and/or have been wounded.
Infections result in the appearance of brown spots on the leaves and stems on the plants. The spots may enlarge and cause malformations of the leaf tissue. Leaves may die and drop from the stems. The symptoms may move from the leaves to the stems as the disease progresses, turning the tissue black and causing it to wilt. The stems infection causes girdling of the tissue resulting in the death of shoots and blossoms.
Infected branches should be pruned 20 to 25 cm (10-12 inches) below the visible infection. Pruning should be done during dry weather to minimize the chance of spreading the pathogen. Pruned branches should be destroyed or discarded. Always sterilize pruning tools between cuts to prevent spreading the bacterium to other areas on the tree.
To prevent further outbreaks, take the proper actions required to keep the plant as healthy as possible. Practice proper fertilization and water management. Stresses caused by the lack of nutrients and/or water can predispose the plants to an infection. Avoid wetting the foliage and overhead irrigation to minimize splashing of the bacterium on to the host plants. Prune plants to allow for increased air circulation through the canopy. Also proper spacing of plants is recommended.
If there are holes in the bark, there may be beetle damage, and the pests will need to be identified before treatment strategies can be recommended.
It sounds as though your lilac may be too far gone to try to save – dealing with both diseases and insect pests can be difficult. If you decide to replace your lilac, try to choose one with some resistance to bacterial blight. Here are a few suggestions:
Syringae oblata var. dilatata ‘Cheyenne’, S. vulgaris ‘Edith Cavelle’, ‘Fr. John L. Fiala’, ‘General Sheridan’,’Katherine Havenmayer’, ‘Krasavitsa Moskvy’, ‘Montaigne’, ‘Nadezhda’, and ‘President Grevy’, S. chinensis ‘Red Rothamagensis’ and ‘Saugeana’ and S. meyeri. Some varieties that show poor resistance characteristics include S. hyacinthiflora ‘Annabel’, S. vulgaris ‘Agincourt Beauty’, ‘Bridal Memories’, ‘Burgundy Queen’, ‘California Rose’, ‘Charles Joly’, ‘Charm’, ‘Edward Boissier’, ‘Edward Gardner’, ‘Etna’, ‘Firmament’, ‘Lavendar Lady’, ‘Little Boy Blue’, ‘Miss Ellen Willmott’, ‘Monge’, ‘Olimpiada Kolesnilova’, ‘Paul Thirion’, ‘Royal Purple’, Ruhm van Horstenstein’, ‘Wonderblue’, and Yankee Doodle’.
Best wishes with your landscape!

Pest & Disease Control for Lilacs

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

NOTE: This is part 5 in a series of 8 articles. For a complete background on how to grow lilacs, we recommend starting from the beginning.

Aphids

They are the size of a pinhead and vary in color depending on the species. Cluster 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 growth media for sooty mold.

Natural Control

  • Sometimes you can knock them off with a strong stream of water from your garden hose.

Chemical Control

  • Bonide® Borer-Miner Killer
  • GardenTech® Sevin® Concentrate Bug Killer
  • Bayer Advanced™ Complete Insect Killer
  • Bonide® Systemic Rose & Flower Care

Euonymous, Lilac, Nannyberry

  • Bonide® Total Pest Control

Leaf Spot

Appears as black or brown spots on underside of leaves. Often the center falls out leaving a hole with a red halo. Leaves may turn yellow and fall.

  • Serenade® Garden Disease Control

Flowering Shrubs

  • Bonide® Copper Fungicide Spray or Dust

Privet, Hydrangea

  • Bonide® Fung-onil™ Fungicide

Leafroller

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

Euonymus, Lilac, Nannyberry

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

Spider Mites

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

Natural Control Hardy Shrubs (thrives with minimal care) * Bonide® All Seasons® Horticultural & Dormant Spray Oil

Euonymus, Lilac, Nannyberry

  • Bonide® Borer-Miner Killer
  • Bonide® Total Pest Control

Mealy Bugs

Adults are 1/4” long, flat, oval shaped with a white waxy covering. Yellow to orange eggs are laid within an egg sac. Crawlers are yellow to brown in color. Over winters as an egg or very immature young in or near a white, cottony egg sac, under loose bark or in branch crotches, mostly found on north side. Damage is by contamination of fruit clusters with egg sacs, larvae, adults and honeydew, which promotes growth of black sooty mold.

Hardy Shrubs (thrives with minimal care)

  • Bonide® All Seasons® Horticultural & Dormant Spray Oil
  • Bonide® Systemic Rose & Flower Care

Euonymus, Lilac, Nannyberry

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

White Fly

Adults are tiny, white winged insects found mainly on the underside of leaves. Nymph emerge as white, flat, oval shapes. Larvae are the size of a pinhead. Suck plant juices from leaves causing them to turn yellow, appear to dry or fall off plants.

Hardy Shrubs (thrives with minimal care)

  • Bonide® All Seasons® Horticultural & Dormant Spray Oil
  • Traps
  • Bonide® Systemic Rose & Flower Care

Euonymus, Lilac, Nannyberry

  • Bonide® Borer-Miner Killer
  • Bonide® Total Pest Control

Bagworm

Bagworms are the larvae of moths. Brown bags up to 2 inches long and composed of bits of dead foliage, twigs and silk are often seen attached to twigs and inside is a dark brown or black caterpillar. Adult female moth is wingless and the male has wings. Severe infestations can defoliate an entire plant often killing evergreens such as arborvitae and cedar but may only slow the growth of a deciduous plant.

Ornamentals

  • Bonide® Thuricide® Bacillus Thuringiensis (BT)

Euonymus, Lilac, Nannyberry

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

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.

Ornamentals

  • Bonide® Thuricide® Bacillus Thuringiensis (BT)

Euonymus, Lilac

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

Anthracnose

Very small, round, brown spots appear first on lower, older leaves. Plants gradually lose leaves from bottom upwards. Other symptoms may include black, sunken spots on leaf stalks, light brown to pale yellow lesions on cane, black fly speck-like spots on green berries.

  • Serenade® Garden Disease Control
  • Fall clean up of fallen leaves and other debris, pruning out infected twigs.

Euonymus

  • Bonide® Fung-onil™ Fungicide

Powdery Mildew

Whitish-gray powdery mold or felt-like patches on leaves and green twigs. Leaves may crinkle and cup upward. Over winters in fallen leaves.

  • Serenade® Garden Disease Control

Viburnum

  • Bonide® Fung-onil™ Fungicide

Botrytis Gray Mold

The fungus thrives in cool, moist conditions. Usually begins on plant debris, weak or inactive plant tissue, than invades healthy plant tissue. Causes spotting and decay of flowers and foliage, tissue becomes soft and watery. Affected parts of plant could wilt and collapse. If humidity remains high a grayish-brown coating and spores develops over the surface of the collapsed tissue.

  • Serenade® Garden Disease Control
  • Good sanitation will help avoid the problem.
  • Remove and destroy dead leaves, flowers and dead plants.
  • Water the plants at soil level and not on foliage.

Black Spot

Disease causing defoliation and black spots on leaves and thrives in moist conditions. Twigs may also be infected. Black spots are circular with fringed margins, if severe, spots can combine to cause a large black mass, can weaken and kill plants.

  • Remove and destroy dead leaves, flowers and dead plants.
  • Water the plants at soil level and not on foliage.

Euonymus, Privet, Spirea, Hydrangea (foliage only)

  • Bonide® Fung-onil™ Fungicide

Downey Mildew

Yellow spots on leaves with downy spots on underside of foliage. Older leaves in center of vine are infected first. Can infect fruits, become soft, grayish, wither, may or may not have downy symptom. Over-winters on fallen leaves, so fall clean up is vital.

  • Serenade® Garden Disease Control
  • Remove and destroy dead leaves, flowers and dead plants.
  • Water the plants at soil level and not on foliage.

Rust

Most common on fern growth after harvest. Infection begins in spring and produces orange stage of disease and is occasionally found on new spears. Yellow or pale orange pustules in concentric ring pattern. Spores are airborne to new fern growth where brick red pustules are formed on all parts of the fern. Ferns may turn yellow or brown, defoliate and die back. In fall the spores turn black and will over winter. Rust causes reduced plant vigor and reduced yields.

  • Serenade® Garden Disease Control
  • Remove infected plant parts and destroy.

Hydrangea (foliage only)

  • Bonide® Fung-onil™ Fungicide

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.

  • Bonide® Systemic Rose & Flower Care

Euonlymus, Lilac, Nannyberry

  • Bonide® Borer-Miner Killer
  • GardenTech® Sevin® Concentrate Bug Killer (exposed)
  • Bayer Advanced™ Complete Insect Killer (exposed)
  • Bonide® Total Pest Control (exposed)

Fall Webworm

Damage the leaves by both feeding and web building. Webworms over-winter within cocoons located in protected places, such as crevices in bark or under debris and fences. Adult moths emerge in summer. They have a wingspan of about 1 1/4″ and vary from pure satiny white to white thickly spotted with small dark brown dots. Females lay white masses of 400-500 eggs on the undersides of the leaves. The caterpillars hatch in 10 days and all from the same egg mass live together as a colony. They spin webs that enclose the leaves, usually at the end of a branch, to feed upon them. After they have defoliated a branch, they extend their nest to include additional foliage.
When caterpillars are mature, they leave the nest to seek a place to spin gray cocoons. The mature caterpillars are about 1 1/4″ long with a broad dark brown stripe along the back, and yellowish sides thickly peppered with small blackish dots. Each segment is crossed by a row of tubercles with long light brown hairs.

  • Prune webbing as it appears.

Ornamentals

  • Bonide® Thuricide® Bacillus Thuringiensis (BT)

Nannyberry, Lilac

  • Bonide® Borer-Miner Killer

Japanese Beetle

Adult is metallic green beetle, which skeletonizes leaves. Larvae are a grub, which feeds on turf roots. This is more of a problem east of the Mississippi River.

  • Bonide® Systemic Rose & Flower Care (adult)

Euonymus, Lilac, Nannyberry

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

Locust

Large (up to 1½ inches long) dark bodied insects with wings. Young insects hatch and enter the soil, where they burrow to the roots. Immature locust suck sap from roots and adults may suck sap from young twigs. Female lays eggs in the sapwood of twigs, causing the leaves on damaged twigs to turn brown. Twigs may break and fall to the ground eventually.

  • Cut off and destroy injured twigs.
  • Maintain good tree vigor by watering and fertilizing plants.

Euonymus, Lilac, Nannyberry

  • Bonide® Borer-Miner Killer
  • Bonide® Total Pest Control

Cutworm

Large (vary from ½ -2” long) fleshy, hairless caterpillars. Adult cutworms are dark, night flying moths with bands or stripes on their forewings and lighter color hind wings. Some feed on the stems, others feed on new tender growth. Cutworms feed at night and can destroy a new plant over night.

Nannyberry, Lilac

  • Bonide® Borer-Miner Killer

Armyworm

Newly hatched worms are white with black heads. Mature worms are light tan or dark brown with dark or orange back and side stripes. They feed on the leaves of plants.

Lilac, Nannyberry

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

In This Series

  • Introduction

Getting Started

  • Acclimate
  • Planting

Care & Maintenance

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

Green Fungus on Lilac Bark

Lilac image by Martha E from Fotolia.com

Lilacs are small shrubs or trees, ranging in size from around 6 to 32 feet in height and are best known for their fragrant flower clusters. They bloom in mid-spring through early summer and are often lilac colored, but can be white, pale pink, yellow or even dark burgundy. They are affected by a variety of pests and organisms such as green lichen, which often is mistaken for a type of fungus on the tree.

Lichen

Lichens are symbiotic organisms of fungus and green or blue-green algae that grow together on trees and other plants. The fungus is able to provide water and nutrients from the air and tree, while the algae are able to provide carbohydrates and photosynthetic foods. They naturally grow on rocks, bark and soil and are harmless to trees and the environment.

Nitrogen

Lichens are natural nitrogen-fixers, capturing nitrogen from the air and adding it to the soil when they begin to decompose, where other plants are able to absorb it. Although both the fungus and alga of lichen are able to live and reproduce separately, this unique ability is only possible when the symbiotic relationship occurs.

Pollution

Lichens are very sensitive to air pollution and will typically not grow in smokey or polluted environments. Scientists now use lichens as a way to test the air quality of specific locations. The University of Illinois states that air pollution made it impossible for lichens to grow in Illinois during the 1970s, but that has begun to change in 2000. Lichens are since very common to Illinois and the Midwestern region of the United States.

Lichen on Bark

As a tree grows in size, lichen are unable to attach themselves to the extending bark. Small patches may develop, consisting of only a few inches. If larger lichens attach themselves to the lilac tree, there is possibly a deeper problem with the tree’s health. A variety of diseases, nutrient deficiencies and pests can reduce a lilac tree’s ability to grow by sapping important resources from the organism.

Lilac Growth

Lilacs that are cured of illness or disease are sometimes able to grow again in time. They need full sun and well-drained soil to properly flower and reproduce. Removing one-third of the oldest stems at ground level ever year for three full years can encourage new growth from the base and help destroy dead, damaged or diseased branches. Lichen should never be removed by hand due to the environmental benefits they provide. Instead, let the organism naturally fall away when the tree starts to develop again; this will provide the soil with added nitrogen and will keep the gardener informed of the tree’s respective health.

Leaf Curl on Lilacs – Knowledgebase Question

Brown rot fungus can be a problem on cherry trees. Upon inspection of your tree, you’ll probably find other signs, as well. The fungal spores survive on diseased twigs and old, rotten fruits and the spores spread by air currents, rain splash and insects. There’s a gummy ooze associated with the infection, and affected twigs and leaves shrivel and die early in the season. To help control this disease, prune and destroy affected twigs and branches. This pruning will also help open the plant up to good air circulation throughout the canopy. Avoid wetting blossoms, foliage and fruit. Be sure to rake and destroy all fallen fruit and leaves at the end of the season. You can apply a Bordeaux mixture (or other copper-containing fungicide), at budswell to help protect the leaves and blossoms from infection. Apply again after the leaves appear. With preventative sprays and good garden sanitation you should be able to keep brown rot under control.
Lilac leaf curl can be caused by a number of fungal diseases. At this point I would recommend raking to remove the infected leaves and waiting until next spring to apply a preventative fungicide (according to label directions).
Best wishes with your landscape!

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