Identifying between limb dieback vs squirrel damage can be difficult, it requires close inspection and taking in several factors to assess the culprit. Squirrel damage is a physical injury caused by chewing bark and twigs, whereas dieback is a gradual symptom of decline originating from disease, stress, or root issues. 

Squirrel Damage

• Chewed Bark and Stripping

Squirrels gnaw through the outer bark to reach the nutritious layer underneath, which can weaken and almost always kill the branch. You’ll often see patches where bark has been physically peeled away leaving the inner layers exposed.

• Dying or Dead Branches

Over time, the cumulative effects of squirrel damage can cause branches to die. We often observe a pattern called ‘flagging,’ where scattered branches in the trees canopy wilt, turn brown, and eventually die while the surrounding foliage remains healthy and green.

• Clipped Twigs on Ground

Another sign of squirrel activity is the scattering of small twigs on the ground beneath the tree. These cuts usually look cleanly clipped or chewed at an angle. 

Canopy/Limb Dieback

• Thinning Canopy

As a tree loses vitality due to biotic or abiotic stress, the leaves in the upper canopy towards the ends of branches will become noticeably smaller than lower canopy leaves. The dieback typically starts at the very outer tips of the upper canopy and gradually works its way inward towards the main trunk over time. 

• Underlying Root or Health Issues 

Commonly triggered by chronic stress conditions, root system issues, over/ under watering, soil compaction, or diseases.  

• Broad, Systemic Pattern

Rather than a single broken branch, dieback often affects entire sections of the canopy, one side, or in the top uniformly. The bark on dead branches usually remains intact initially until the branch decays to a point in which the bark may flake off later.