1. ANTHRACNOSE
May infect leaves, twigs, buds, shoots, and even the fruit of various landscape trees
Raking and removing infected leaves will remove the main source of spores that could infect the tree next spring
Anthracnose may cause defoliation on most maple, oak, elm, walnut, birch, sycamore, and hickory trees. Occasionally, it can affect ash and linden trees.

2. Apple Scab
Most severe during spring and early summer when the humidity is high and the temperature is moderate
Most obvious symptoms occur on leaves and fruit in the spring and summer, and look like small velvety brown-olive green spots that enlarge and darken to become more or less circular

3. Black spot
Roundish black spots with fringed margins that can be up to ½’’ in diameter
Spots form on the upper sides of leaves
The disease is caused by a fungus called Diplocarpon rose
To control black spots, rake fallen leaves and remove infected canes
Avoid wetting leaves when watering and maintain air circulation around within the plants to promote drying

4. Botrytis MANAGEMENT Commonly called gray mold
Remove dead or dying tissue from the plants and from the soil surface
Heat and ventilate greenhouses to prevent high humidity conditions
Avoid injuring plants in any way
Found virtually everywhere plants are grown
Can attack many different types of plants
Signs of Botrytis:
Fading flowers
Leaves on which fading infected flowers have fallen
Broken stems or injured leaves
Commonly called gray mold

5. Canker Symptoms Management
Brown/reddish lesions on the bark of trunks or branches, or as injured areas on smaller twigs
New leaves appear smaller than normal, often curled or sparse, and pale green/yellow/brown in color.
Common, widespread, and destructive to a wide range of trees and shrubs
Management
Keep plants healthy through proper planting, mulching, watering, soil management, pruning, and winter protection practices
Do not prune when bark is wet
Avoid all unnecessary bark wounds

6. Cedar-apple rust Control Fungicides Using resistant varieties
Can defoliate trees and blemish fruit making them unmarketable
Before an apple can be infected, adequate moisture must be present in a temperature range from 46-75F to allow for formation of basidiospores on cedar galls
Leaves are most susceptible to infection when 4-8 days of age
Fruit are susceptible from tight cluster through bloom

7. Crown Gall Management Avoid wounding plants near the soil line
Can infect a wide range of herbaceous and woody plants
Usually restricted to the roots, lower stems, and lower branches of infected plants
Caused by the soil-borne bacterium Agrobacterium tumefaciens
Management
Avoid wounding plants near the soil line
Prune infected plants (Disinfect cutting tools between each cut)

8. Fireblight Symptoms Dead branches Water-soaked blossoms Management
A bacterial disease that can kill branches and whole plants of many members of the rose family, including apple, pear, quince, and crabapple
Can be spread by insects, splashing rain or contaminated pruning tools
Symptoms
Dead branches
Water-soaked blossoms
Light brown/blackened leaves
Discolored bark
Black “shepherd’s crook” twigs
Dried fruit
Management
Pruning (Sterilize all tools after each cut)
Chemical Sprays

9. Powdery mildew Management Avoid overhead watering
Remove and destroy all infected plants
Prune overcrowded material
Looks like powdery splotches of white or gray, on the leaves or stems of plants
Different powdery mildew fungi infect different plants
Causes
Dampness
High humidity
Crowded plantings
Poor air circulation
Lilacs, crab apples, phlox, monarda, roses, grapes, squash and cucumbers are all likely targets for powdery mildew

10. Root rot Symptoms Appear overwatered or droopy
Brown, slimy, smelly roots
Plant leaves start turning yellow
Plants drink much less water than usual
Plants affected by root rot will start losing their leaves, yellowing, drooping, and look like they’re dying
Affected plants will drink less water
Management
Keep growing area clean
Add beneficial bacteria to the water
Try to get as much oxygen as possible dissolved in the water