Trees still suffering from 2011's drought, can fall after storms

Published on Friday, 23 May 2014 23:26 - Written by Faith Harper fharper@tylerpaper.com

Regina Galliardt was busy cleaning her garage last week when she heard loud crackling sounds, followed by a boom.

Mrs. Galliardt, who lives in the 1400 block of Sequoia Street in Tyler, said the neighborhood commotion came from across the street, where winds knocked down a tall red oak tree into a neighbor’s home.

The wind took it down with such gusto that the roots were pried from the soil and were sticking out to the side.

The tree’s owner, Frank Prater, said it was on the lot when they built their home 46 years ago, and based on the number or rings, could be about a century old. The oak towered about 100 feet into the air and was prone to dropping pieces in wind and storms.

“The shade is wonderful in the summertime, but when the wind comes through, it does a lot of damage,” he said.

Local arborists said they have received several calls of downed trees after rainstorms, when the ground is wet and the wind has been strong, which makes already weakened trees more likely to fall.

They said some trees have not recovered from the 2011 drought, and once a tree is weakened, a chain reaction of factors causes its demise.

Trees do not recover quickly from damage, and even though their leaves might be green, there could be problems under the ground, said Daniel Duncum, an arborist with the Texas AgriLife Extension Service in Longview.

“We humans are past 2011,” he said of the year’s severe drought. “We are in 2014, and that was old history, but it really affected those trees and it still affects them today.”

Trees grow slowly, but they also recover slowly from shock, and deaths can be attributed to the drought for five or six years after, according to local tree experts.

“Trees get stressed, and once a tree is stressed to a certain degree, they lose their vigor and number of secondary factors come into play that affect the biological functions of the trees,” said Eric Artmire, a private Tyler arborist with Artmire Urban Forestry.

Artmire said droughts can cause tissue and root damage. Trees do not keep a reservoir of water in their trunks, and water is constantly moving through a healthy tree, Artmire said.

“When soil gets dry for an extended period of time, its absorbing roots, the small, tiny roots of the tree — they die,” he said. “That’s not the end of the world because a tree is constantly growing new absorbing roots every year, but when they can’t be generated as fast as normal and all of sudden you have a huge ratio (of roots) that have died, that puts that tree in a higher level of stress.”

Most of the underlying root structure and anchoring mechanisms of trees are within the upper 12 inches of soil, and other factors can affect how well the tree can absorb water and anchor itself.

“Another key point for a tree is to pull up moisture from the soil, the soil has to have more moisture than the absorbing root of that tree — it’s like a sponge effect,” Artmire said, adding grass roots are much more shallow and pick up water much faster than trees.

The drought also caused the ground to heat up tremendously, essentially cooking the roots of trees that did have enough leaf litter on the ground or a canopy of leaves to shade its roots.

Once a tree is weakened, there is also a possibility for bugs, bacteria and fungi to set in.

It usually takes a combination of factors for them to teeter over, said Jason Ellis, certified arborist and district forester for the Texas Forestry Service in Jasonville.

Certain species such as live oak, Bradford pear and pine trees are more susceptible to windthrow, but Ellis said each tree is an individual.

“You can have a tree that is marked really high as far as being wind-resistant, but if that tree is having a problem in its root system or if it’s in a bad site, it can still blow over,” he said.

Ellis likened the stability of a tree to a wine glass, where the crown of the tree is the vessel, the trunk is the stem and the roots are the base.

If trees’ roots are not properly anchored or getting washed out by too much water or poor drainage, they are susceptible to windthrow. Other actors are parasites and root rot, Ellis said. Mushrooms or nodes at the base of the tree indicate issues with the roots.

The phenomenon is more likely to happen in the spring or summer when the leaves are full. The leaves act like a sail in strong winds.

Arborists also recommend not building on top on tree roots. Sidewalks, retaining walls and sidewalks on top of their roots can kill them slowly.

Ellis said anyone who thinks there is an issue with a tree should call a certified arborist. The International Society of Arboriculture has list atwww.isa-arbor.com .

Neighbors on Sequoia Street said the tree caused some commotion, but they were thankful no one was injured.

“It’s definitely worth noting that if we have had a bunch of rain to watch out for popping sounds,” Mrs. Galliardt said.