Energy & Environment

A disease is killing forest and shade trees in the Houston area

The pathogen is known as laurel wilt, and mainly affects red bay, sassafras, avocados, swamp bay and other related trees.


Dave Appel of Texas A&M AgriLife
Brown, withered leaves on red bay trees in the Kingwood residential area near Houston indicate laurel wilt.

A tree disease is currently spreading throughout east Texas and is now killing off forest and shade trees in the Houston area, according to Texas A&M AgriLife experts.

The pathogen is known as laurel wilt, and mainly affects the Lauraceae tree family, which includes red bay, sassafras, avocados, swamp bay and other related trees. The initial symptoms of an infected tree are yellowing and wilting of leaves in random branches. It was first found in Texas in 2013, and has been reported in at least 14 east Texas counties.

David Appel, a plant pathologist at Texas A&M, said several trees in the Kingwood area have fallen victim to the pathogen in recent months. He added that he expected the pathogen to rapidly spread this summer, and that the situation would likely require serious attention.

“It’s going to continue spreading as it has been, and that is from one property to the next,” he said. “So what we’ll see is expansion in the locations where it’s already occurring, as well as probably we’re going to see new locations where it’s popping up.”

Laurel wilt can be spread through the roots of one tree to another or by insect, specifically, a bullet-shaped beetle called the redbay ambrosia beetle — one of many wood-boring beetles found around Greater Houston. Appel said the beetles are uniquely suited to acquire the fungus from dead trees and transmit it to healthy trees.

“These beetles have developed a symbiotic relationship with the fungus,” Appel said. “After the tree dies, the fungus proliferates…and (the beetles are) able to eat the fungus.”

Appel added that the pathogen would likely continue to be an issue in east Texas due to the region’s large population of red bay trees. As more trees succumb to the disease, Appel advised against transporting infected wood, and suggested fungicide injections for trees that are exhibiting symptoms of laurel wilt.

“We can expect it is going to continue to keep spreading and keep killing trees and influencing people’s property value,” he said. “It is important to get that wood destroyed once it’s identified as having been infected.”

Lucio Vasquez

Lucio Vasquez

Newscast Producer

Lucio Vasquez is a newscast producer at Houston Public Media, NPR’s affiliate station in Houston, Texas. Over the last two years, he's covered a wide range of topics, from politics and immigration to culture and the arts. Lately, Lucio has focused his reporting primarily on public safety and criminal justice...

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