Plant Ice Resistant Trees

Via the Tree Care Industry Association,

A number of characteristics increase a tree species’ susceptibility to ice storms: “included” bark, decaying or dead branches, increased surface area of lateral (side) branches, broad crowns, and imbalanced crowns.

Included bark results from in-grown bark in branch junctions. This is a weak connection and enhances a tree’s susceptibility to breakage under ice-loading conditions. For example, “Bradford” pear branches often break during ice storms where there is included bark in branch junctions. In contrast, the “Aristocrat” pear has few branches with included bark and sustains less damage during ice storms.
Decaying or dead branches are already weakened and have a high probability of breaking when loaded with ice. The surface area of lateral branches increases as the number of branches and the broadness of the crown increase. With an increased surface area, more ice can accumulate on lateral branches; the greater ice load results in greater branch failure.

Many broad-leafed tree species, when grown in the open, form broad crowns (decurrent branching), increasing their susceptibility to ice storms. Examples includes Siberian elm, American elm, hackberry, green ash, and honey locust. Trees with imbalanced crowns are also more susceptible to ice damage.

Ice storm damage management and prevention
Proper tree placement, away from structures, will reduce property damage. Trees should not be planted in locations where growth will interfere with above-ground utilities – branches that grow into power lines and fail during ice storms create power outages and safety hazards. Trees pruned regularly from a young age should be more resistant to ice storms as a result of removal of structurally weak branches, decreased surface area of lateral branches, and decreased wind resistance.
Professional arborists can install cables and braces to increase a tree’s tolerance to ice accumulation in situations where individual trees must be stabilized to prevent their failure.
After storm damage has occurred, hazardous trees and branches require immediate removal to ensure safety and prevent additional property damage. Trees that can be saved should have broken branches properly pruned to the branch collar (stubs and flush-cut pruning result in weakly attached sprouts and future insect and disease problems). Loose bark should be cut back only to where it is solidly attached to the tree. A split fork can be repaired through cabling and bracing.

Tree species resistant to ice damage can be planted to reduce tree and property damage from ice storms:
Ice storm susceptibility of tree species commonly planted in urban areas
Susceptible:
• American elm • American linden • Black cherry • Black locust
• Bradford pear • Common hackberry • Green ash • Honey locust
• Pin oak • Siberian elm • Silver maple

Intermediate resistance:
• Bur oak • Eastern white pine • Northern red oak • Red maple
• Sugar maple • Sycamore • Tulip tree • White ash

Resistant:
• American sweetgum • Arborvitae • Black walnut • Blue beech
• Catalpa • Eastern hemlock • Ginkgo • Ironwood
• Kentucky coffee tree • Littleleaf linden • Norway maple • Silver linden
• Swamp white oak • White oak

(Source: University of New Hampshire, University of Illinois, USDA Forest Service and NH Dept. of Resources and Economic Development.)

Find a professional:
If you are in Connecticut, give us a call at 1-800-690-2726.
If you are elsewhere, call the TCIA at 1-800-733-2622 or do a ZIP Code search on their website.

1 Comment »

  1. Tweets that mention Arbor Services of Connecticut » Plant Ice Resistant Trees -- Topsy.com said,

    February 5, 2011 @ 12:59 am

    [...] This post was mentioned on Twitter by Tree Care Industry, Arbor Services of CT. Arbor Services of CT said: New (timely) blog post about planting ice-resistant species! Connecticut is icy today. bit.ly/eZN0He (via the @VoiceOfTreeCare) [...]

RSS feed for comments on this post · TrackBack URI

Leave a Comment