The unforgiving Texas drought has killed 100 million to 500 million trees statewide, according to a preliminary survey by the Texas Forest Service.
The devastation is equivalent to 2 to 10 percent of the estimated 4.9 billion trees on 63 million acres of woodlands in Texas, said Chris Edgar, a forest resource analyst. Land is considered forested if it has at least 10 percent coverage of tree canopy, he said.
"We were surprised by the number," he said. "We were hearing reports, and as I drive around the state, I've seen mortality that in some cases is quite extensive. To see these numbers it really brings it home."
And those figures don't include losses in urban areas or trees destroyed by wildfires that scorched nearly 4 million acres this year.
"We don't have anything that we can compare to this mortality," Forest Service director Tom Boggus said. "This will probably set a benchmark."
Boggus started working for the agency in the 1980s during a drought that killed trees, but it was nothing like this, he said.
"What's significant is it's statewide. That's the big difference."
The drought wasn't the only culprit -- the hottest summer on record and prolonged high winds helped sap trees, he said, calling it the same "perfect storm" of conditions that ignited the record fire season.
In September, the nonprofit Trees for Houston estimated that 66 million trees, or about 10 percent of the canopy in the eight-county Houston area, would die within two years because of the drought.
In Fort Worth, city forester Melinda Adams said, there has been high mortality in parks where trees lacked supplemental water.
"We did a preliminary inventory, and we came up with a little more than 500 trees," she said. "We have seen some losses in residential areas, but the big losses are in the parks."
The losses could have been much worse, Adams said.
"If you watch the drought maps, we didn't get hit as hard as the rest of the state," she said. "Our trees are used to only 32 inches of rain a year, so the trees here are more drought-tolerant than trees in Houston that get a lot more rainfall."
The summer heat was also deadly for many thin-barked trees such as red oaks and dogwoods, she said.
"All those 100-degree days were just too much for them," she said, noting that the city is removing dead trees that pose a hazard.
"We've gotten a lot of water recently, and I'm hoping those that were marginal will be bouncing back this spring," Adams said.
Across the state, junipers, commonly called cedars, have been hard hit in multiple areas, particularly West Texas, the forest service said.
Loblolly pines, the state's primary commercial timber source, have died by the millions around Houston and in East Texas. In Central Texas around Bastrop and Caldwell counties, eastern red cedars and post oaks have suffered, as have hardwood forests in Northeast Texas.
Agency foresters plan to use satellite imagery to conduct a more in-depth analysis in the spring, which is when trees that may have gone into early dormancy -- an act of self-preservation -- attempt a comeback.
A more scientific long-term study will be completed as the agency collects data through its forest inventory and analysis program, Boggus said.
The federally funded tree census allows the forest service to track how trees are growing and changing. But Texas is so vast and some forested areas so remote that a full inventory takes a decade to complete.
Boggus worries that all the dead trees will provide more fuel when the next fire season erupts.
"That's our big question," he said. "From Fort Worth down along the Interstate 35 corridor to Austin, where you have all these dead junipers, it's going to be a real concern.
"It won't take much to create really dangerous fires."
Steve Campbell, 817-390-7981