By Jim Forsyth
SAN ANTONIO (Reuters) - The massive drought that has dried out Texas over the past year has killed as many as half a billion trees, according to estimates from the Texas Forest Service.
"In 2011, Texas experienced an exceptional drought, prolonged high winds, and record-setting temperatures," Forest Service Sustainable Forestry chief Burl Carraway told Reuters on Tuesday. "Together, those conditions took a severe toll on trees across the state."
He said that between 100 million and 500 million trees were lost. That figure does not include trees killed in wildfires that have scorched an estimated 4 million acres (1.6 million hectares) in Texas since the beginning of 2011. A massive wildfire in Bastrop, east of Austin in September that destroyed 1,600 homes, is blamed for killing 1.5 million trees.
The tree loss is in urban and rural areas and represents as much as 10 percent of all the trees in the state, Carraway said.
"This is a generational event," Barry Ward, executive director of the nonprofit Trees for Houston, which supports forestry efforts, told Reuters on Tuesday. "Mature trees take 20 or 30 years to re-grow. This will make an aesthetic difference for decades to come."
He said the loss will affect the state in many ways. For example, there is increased fire danger because all the dead trees are now fuel, Ward said.
Scattered rain and snow has only recently put a dent in the historic drought. The one-year period between November 1, 2010, and October 31, 2011, was the driest in the state's history, according to State Climatologist John Nielsen-Gammon.
Along with the drought has come punishing heat. The National Weather Service said the months of June through August in Texas were the hottest three-month period ever reported by any state in U.S. history.
The drought and heat caused many trees to go into dormancy in the middle of the summer as a self-preservation measure, leaving them without adequate nourishment, said forester Clay Bales of the Texas Forest Service.
Officials say the dead trees include all types, from pine to deciduous trees, and the carnage is state-wide.
The Texas Forest Service says aerial mapping will be used in a more in-depth study in the spring, to see whether any of the trees that have gone into early dormancy may bounce back. But with 63 million acres (25 million hectares) of forest land in the state, it could take as long as 10 years to get a real inventory of the damage from the drought.
Forest Resource Analyst Chris Edgar said trees and forests are amazingly resilient.
"Loss of trees due to adverse weather conditions is something that is a part of the natural process of the forest," said Edgar, who works for the Texas Forest Service.
One of the worst-hit areas is in a part of east Texas known as the Piney Woods, he said. That is one of the country's leading producers of wood and paper products. It is still unclear what the long-term damage may be to that industry, which is one of the largest agricultural employers in the state.
Carraway said that what Mother Nature has damaged, Mother Nature can repair.
"Assuming the rainfall levels get back to normal, I certainly see the forest being able to recover," he said.
(Editing by Corrie MacLaggan and Greg McCune)