TreeIssues

Pest & Disease Forecast for Montana

It's September — 25 tracked threats are active right now in Montana. Each timeline shows estimated activity across the year.

Active nowWatch closely — these threats are at or near peak activity this month.
Mountain Pine Beetle
InsectCRITICAL

Peak activity: Summer

J
F
M
A
M
J
J
A
S
O
N
D
Ips Bark Beetles
InsectMODERATE

Peak activity: Summer

J
F
M
A
M
J
J
A
S
O
N
D
Dutch Elm Disease
DiseaseCRITICAL

Peak activity: Spring

J
F
M
A
M
J
J
A
S
O
N
D
Powdery Mildew
FungusLOW

Peak activity: Spring

J
F
M
A
M
J
J
A
S
O
N
D
Armillaria Root Rot
FungusHIGH

Peak activity: Spring

J
F
M
A
M
J
J
A
S
O
N
D
Dothistroma Needle Blight
FungusMODERATE

Peak activity: Spring

J
F
M
A
M
J
J
A
S
O
N
D
Cytospora Canker
FungusHIGH

Peak activity: Spring

J
F
M
A
M
J
J
A
S
O
N
D
Bronze Birch Borer
InsectHIGH

Peak activity: Summer

J
F
M
A
M
J
J
A
S
O
N
D
Asian Longhorned Beetle Damages hardwood trees by tunneling deep into trunks and branches
InsectMODERATE

Peak activity: Summer

J
F
M
A
M
J
J
A
S
O
N
D
conical brittlestem
FungusMODERATE

Peak activity: Spring

J
F
M
A
M
J
J
A
S
O
N
D
Asian Lady Beetle
InsectMODERATE

Peak activity: Summer

J
F
M
A
M
J
J
A
S
O
N
D
Police Car Moth
InsectMODERATE

Peak activity: Summer

J
F
M
A
M
J
J
A
S
O
N
D
Black Damsel Bug
InsectMODERATE

Peak activity: Summer

J
F
M
A
M
J
J
A
S
O
N
D
Cedar-Apple Rust
FungusMODERATE

Peak activity: Spring

J
F
M
A
M
J
J
A
S
O
N
D
Black Witch
InsectMODERATE

Peak activity: Summer

J
F
M
A
M
J
J
A
S
O
N
D
Bronze Ground Beetle
InsectMODERATE

Peak activity: Summer

J
F
M
A
M
J
J
A
S
O
N
D
Punctured Tiger Beetle
InsectMODERATE

Peak activity: Summer

J
F
M
A
M
J
J
A
S
O
N
D
Transverse Lady Beetle
InsectMODERATE

Peak activity: Summer

J
F
M
A
M
J
J
A
S
O
N
D
Thirteen-spotted Lady Beetle
InsectMODERATE

Peak activity: Summer

J
F
M
A
M
J
J
A
S
O
N
D
Seven-spotted Lady Beetle
InsectMODERATE

Peak activity: Summer

J
F
M
A
M
J
J
A
S
O
N
D
Monarch
InsectMODERATE

Peak activity: Summer

J
F
M
A
M
J
J
A
S
O
N
D
Soft-lined Wave
InsectMODERATE

Peak activity: Summer

J
F
M
A
M
J
J
A
S
O
N
D
Small Milkweed Bug
InsectMODERATE

Peak activity: Summer

J
F
M
A
M
J
J
A
S
O
N
D
Greater Sulphur-cup Lichen
FungusMODERATE

Peak activity: Spring

J
F
M
A
M
J
J
A
S
O
N
D
Spotted Tussock Moth
InsectMODERATE

Peak activity: Summer

J
F
M
A
M
J
J
A
S
O
N
D
← National forecast|All Montana threats →|Get monthly care reminders →

Activity windows are seasonal estimates based on pest type and known phenology for the continental US; local timing varies with weather and elevation. Always confirm with a certified arborist or your state extension office.