September 28 2012


Trees are terrific: they help shade and cool our homes and neighborhoods, break cold winds to lower our heating costs, and breathe life-giving oxygen into our atmosphere. They also just make us feel good. Unfortunately, trees can also be hazardous.

Hurricanes, tornadoes, and heavy winds can uproot or snap trees and bring down heavy branches. Remember last summer’s violent dericho? During that ferocious storm, downed trees dominated the news reports, and indeed, many were deadly.  In New Jersey alone, six people were killed by falling trees.

So ask yourself the question: are your trees healthy enough to withstand wild weather? Or are they “hazard trees”?


Hazard trees are defined as trees with defects that weaken their structural integrity, giving them the potential to strike a “target”. A target is anything of value such as a person, car, or house.

Which types of trees are most hazardous?

1) Large trees with limited root zones or damaged roots, often caused by ground saturation.

2) Trees with thick, heavy canopies. Some species are particularly susceptible to wind damage, including Bradford pears, maples, and white pines.

3) Trees with weak branch unions, where branches meet shaped like a “V” rather than a “U”.

4) Trees with two or more dominant trunks.

5) Trees with pre-existing structural damage.

The best insurance policy against hazards is long-term tree maintenance. Remember, any tree can fail during a storm. But investing in good tree care right from the get-go can reduce the risks.

The following tips will help give your trees a healthy start:

  • When first planting, remember to choose the right tree for the right place. Otherwise, you may need to remove the tree sometime in the future if it has the potential to strike a target.
  • During construction, take care not to injure the tree or its roots. Synthetic burlap material surrounding the root ball can constrict future root growth and also choke–and weaken–the tree trunk. Cut away as much of it as possible.
  • Once the tree is ready for pruning, prune wisely to promote good structure. Limbs broken in a storm or dead branches can be removed at any time. Never top a tree. Topped trees are more likely to break apart in storms than trees that retain their natural shape.


Inspect trees at least once a year and after severe storms.

First, check the following four BASIC characteristics of tree vigor: 1) new leaves or buds 2) leaf size 3) twig growth and 4) absence of crown dieback (gradual death of the upper part of the tree). Flag any signs of weakness or abnormalities.

Next, examine tree roots, trunk flare (where roots spread), main stem, branches, and branch unions on all sides for defects. Use binoculars to inspect branches of large trees.

Some defects in hazard trees include:

  • Dead branches
  • Spotted, deformed, discolored, or dead leaves and twigs
  • Vertical cracks
  • Rot
  • Insect activity
  • Weak branch unions
  • Trunk decay
  • Crown dieback
  • Loose bark or deformed growths, such as trunk conks (mushrooms), are common signs of stem decay
  • Cankers (localized dead areas)
  • Root problems
  • Poor tree structure (sometimes caused by over-pruning or topping)



Prune when necessary to remove dead, diseased, or insect-infested branches and to improve tree structure, enhance vigor, or maintain safety. Prune sparingly, since even proper pruning stresses the tree. Remove no tree branch without a reason.


Tree topping is the most expensive and detrimental form of pruning. Topping a tree creates large wounds that allow rot and fungal decay to enter the tree. This not only can damage the tree’s appearance, it can reduce the tree’s life expectancy by weakening its structure.


During drought, water trees sufficiently. Drought-stressed trees are more susceptible to pests and diseases.



Mulch your trees in a “donut” rather than piled up against the tree trunk in a “volcano” shape. Mulching in a “volcano” shape can make the tree more susceptible to fungus, insects, and rodents.



Tree removal is a last resort. Arborists usually recommend it only when a tree is:

  • dead, dying, or considered irreparably hazardous.
  • causing an obstruction or is crowding and causing harm to other trees, and the situation is impossible to correct through pruning.

For further information and advice about the health and safety of your trees, contact our NJ landscaping company or a Certified Tree Expert (CTE).

And for additional tree facts, click on the New Jersey Department of Environmental Protection.