| AFFECTING LEAVES: |
|
CONDITION
|
CAUSE
|
 |
Yellow,
raised pouches |
Eriophyid mites
|
 |
Orange
spots |
Juniper rusts (Gymnosporangium
spp.)
|
 |
Rusty
scabs on leaf |
Blister mite. See Eriophyid mites.(Phytoptus
spp.)
|
 |
Chewing
leaves |
Pearslug (Caliroa
cerasi)
|
 |
Aphids |
Apple aphid (Aphis pomi)
|
 |
Blackened
and wilting leaves |
Fireblight (Erwinia
amylovora)
|
|
| AFFECTING TWIGS AND SMALLER BRANCHES: |
|
CONDITION
|
CAUSE
|
 |
Aphids |
Wooly aphids (Eriosoma
sp.)
|
 |
Scales |
Oystershell scale (Lepidosaphes
ulmi) or Mealybug (Phenacoccus spp.)
|
|
| AFFECTING LARGER BRANCHES OR TRUNK: |
|
CONDITION
|
CAUSE
|
 |
Blackened,
wilting, and crooked tips |
Fireblight (Erwinia
amylovora)
|
 |
Discolored
areas and dead bark containing small pimple-like fruiting bodies
(pycnidia) |
Cytospora canker (Valsa
spp., Luecostoma spp.)
|
 |
Large
dead and discolored areas on southwest side of trunk |
Winter sunscald
|
 |
Clear to
white oozing or frothy malodorous liquid exiting from wounds |
Bacterial wetwood and
slime flux
|
 |
Borers |
Flaheaded appletree borer
(Chrysobothris femorata)
|