Mature trees should be inspected on a regular basis, preferably yearly. Do
this safely from the ground, using binoculars if necessary. Loss of vigor is
the surest early warning sign there may be a problem with your tree. Advice
from an arborist may be invaluable and a great yearly deposit on your long term
What To Look For During An Inspection
A healthy tree shows it! Here are some signs your tree is growing
Health and vigor
Tree species grow at different rates, so make sure your tree is growing appropriately.
Check for new buds and leaves in spring, appropriate leaf size, twig growth, and
a full crown. Trees in good condition will have full crowns, vigorous branch
growth, and full-sized leaves with good coloring and condition.
Most trees should have a strong upright central leader with well-attached, well-spaced, balanced branches. Pruning for structure should begin while the tree
is young to develop good form for future growth.
Right Tree, Right Place
Know the size your tree will grow and make sure it will not interfere with power
lines, infrastructure, or buildings.
Regular inspection can prevent some tree failures, but not all failures are
predictable or preventable. If you suspect a problem, it is best to get a professional
evaluation. Here are some common warning signs:
Leaning results from sudden loss of root anchorage. Check your tree's vertical
position to see if roots are exposed on the opposite side of a lean. Leaners
are imminent hazards because they can fall at any time.
Weakly Attached Branches
Inspect large branches for splits where they attach to your tree and areas
where many branches arise from the same point on a trunk. Both indicate potentially
hazardous and weak branches and have a high chance for failure. Often these
types of branches will need to be removed.
Also called codominant stems, these trunks are weakly attached and prone to
split apart. These codominant stems will grow to be a problem if not dealt with.
Cavities and Evidence of Decay
Decay in pockets on branches, or in old wound cavities, and mushrooms or conks
on trunks or on roots at the base of your tree may indicate hazardous conditions
and potential structural failure. An arborist should be called to evaluate your
Trunk and Branch Cracks
Cracks can be vertical or horizontal. Cracks in the bark are typically not
a problem; cracks into the wood are cause for concern. An arborist should inspect
your cracks to determine depth and severity of damage. In some cases corrective
pruning can reduce potential hazards by lightening the load on the base branch
Broken branches or "hangers" are likely to fall without warning and
could cause serious damage. They should be removed immediately.
Branches that have died will eventually fall off. Small branches usually should
not cause concern, but dead branches larger than 2" in diameter should