Trees going to extremes to survive heat

LONGVIEW, TX (KLTV) - By Bob Hallmark - bio | email
Posted by Ellen Krafve - bio | email | Twitter

LONGVIEW, TX (KLTV) - It is a phenomenon that East Texans have reported recently that deals with the intense heat and tree limbs crashing to the ground. For lack of a better term, it is called "limb drop" and it is a strange occurrence that has several factors involved that helps trees survive.

"This is a mechanical action...primarily based little moisture in the tree," explained Daniel Duncum, with the Longview Urban District Forestry Department. "We haven't had the rain. The roots don't have the water to pick up."

The theory is that trees prune themselves in extreme drought over a period of years.

"The drying wood can begin to crack internally," explained Duncum. "You won't see it on the outside, but do that a couple of times - two or three years in a row - and all of the sudden you've got a weak point in the limb."

It is not just summer. The weight of snows in the winter weaken the branches. Leaves and needles become sails in even a light wind, and the weakened branch falls away. The phenomenon can be dangerous. Trees can sometimes drop limbs weighing several hundred pounds. There have been reported deaths from this limb drop in the past.

"If you're outside, you're a target," said Duncum. "Your house may be a target, a fence, a car, neighbor, somebody going by on the street."

The bottom line is to check your trees for broken branches.

"There is a potential that these things could come down," said Duncum.

The Forestry Service says to prevent limb drop in extreme drought conditions. You should make sure your trees get around and inch and a half of water each week. Any branches that appear to be cracked or sagging should be cut away.

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