In Central Texas, an urban tree canopy bends to the ice

Joe Rendon, a worker with Medxcel, cuts off a broken tree limb near Ascension Seton Medical Center on Thursday after an ice storm caused power outages across Austin. (Credit: Evan L'Roy/The Texas Tribune)

AUSTIN — All day and all night after the ice storm struck, Austin residents listened for the cracks, splinters and crashes. Each crack of a falling limb could shut the power off — if their home hadn’t gone dark already.

“It’s a really, really thick layer of ice,” said Jonathan Motsinger, the Central Texas operations department head for Texas A&M Forest Service. “Trees can only support weight to a certain extent, and then they fail.”

Across the Texas Hill Country this week, trees snapped under the weight of ice that accumulated during multiple days of freezing rain. Some of the most iconic trees were among the most severely damaged: live oaks (some of them hundreds of years old), ashe junipers (the scourge of allergy sufferers during “cedar fever” season), cedar elms. As their branches gave way, they took neighboring power lines with them.

“The amount of weight that has accumulated on the vegetation is probably historic, extreme,” Austin Energy general manager Jackie Sargent said during a Thursday press conference.

Ice can increase the weight of tree branches up to 30 times, said Kerri Dunn, a communications manager for Oncor. The utility reported that almost 143,000 of its customers in North, Central and West Texas were without power Thursday afternoon.

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“Trees are the No. 1 cause of outages when you have ice storms,” Dunn said. “We can’t always prevent [trees] from falling in the wrong direction and hitting our equipment.”

Nearly 153,000 Austin Energy customers were without power Thursday afternoon, and the utility said it is unable to provide an estimate for how long it will take to fix all of the broken lines.

Proper pruning and maintenance of trees in the paths of power lines are the responsibility of Austin Energy, the city’s electric utility that is overseen by the Austin City Council. But city officials said residents are responsible for trimming trees that are not in utility easements but are close enough to power lines to fall on them during storms. Tree pruning can cost hundreds or thousands of dollars.

Certain trees are more likely to suffer broken limbs and split trunks during ice storms, Motsinger said. Live oaks, one of the most common trees in Central Texas, tend to keep leaves throughout the winter — which means they collect more ice than trees that drop their leaves in the fall. As evergreens, ashe junipers have the same problem in ice storms.

Motsinger said the historic drought last summer may have caused trees to have more dead limbs than usual, which are more likely to break when caked with ice. But in general, Motsinger said, the drought probably had less of an impact than the sheer amount of ice.

Proper tree maintenance could have prevented some of the destruction, he said.

Utilities have plans for managing trees and other vegetation around power lines, said Ben Gaffaney, spokesperson for the Association of Electric Companies of Texas. He said he heard tree limbs falling around his home Wednesday.

But those plans are sometimes hampered by local policies, said Sargent, the Austin Energy general manager. Efforts to avoid disturbing bird habitats and to avoid spreading the fungal disease oak wilt during certain times of the year can slow pruning efforts and are among the “biggest barriers” to trimming, an Austin Energy spokesperson told The Texas Tribune.

Sargent said during a press conference that the utility would discuss city regulations that prevent better pruning with local leaders.

In some cases, the utility also has to fight public pushback when it prunes trees around power lines — residents sometimes complain about the utility lopping off large limbs. The Austin Energy spokesperson said that between 40% and 50% of Austin homeowners delay the utility’s trimming work with questions or disputes about trimming plans.

Michael Webber recalled how residents resisted tree-trimming efforts when he served from 2008-13 on the electric utility commission that oversaw Austin Energy. It left the utility in a tough spot: No one liked tree trimming, but no one wanted to lose power during a storm either, he said.

Webber, now an energy resources professor at the University of Texas at Austin, said his own street west of Austin was impassable Thursday because of downed branches, and a colleague is mourning her broken 150-year-old live oak.

Austin Energy is one of the few utilities in the nation that attempts to meet with property owners in advance of tree trimming, according to the city of Austin. The utility notifies neighborhood associations and leaves work plans at people’s doors. When property owners don’t respond, the utility sends letters to notify homeowners and proceeds with its trimming plan.

“We could really use help in that area with getting our residents to understand the importance of vegetation management to allow our crews in,” Sargent said. The utility’s general manager added that Austin Energy has increased its tree-trimming budget in recent years. Austin City Council in 2021 doubled the utility’s budget for vegetation clearing, according to the utility’s website, but there is a backlog of trimming work to be done.

Austin has almost 34 million trees in the city, according to an online tree census maintained by Texas A&M Forest Service and the U.S. Forest Service.

“It’s a big point of pride,” said Keith Mars, who oversees the city of Austin’s Community Tree Preservation Division.

Mars said that shade from the trees saves Austin residents millions of dollars a year in energy costs by cooling homes during hot summer days.

“Trees are infrastructure,” Mars said. “How much maintenance and how much care we provide, so that [the trees] can continue providing those other benefits, is the kind of tradeoff that we all have.”

Sneha Dey contributed to this story.

Disclosure: Association of Electric Companies of Texas, Oncor and University of Texas at Austin have been financial supporters of The Texas Tribune, a nonprofit, nonpartisan news organization that is funded in part by donations from members, foundations and corporate sponsors. Financial supporters play no role in the Tribune’s journalism. Find a complete list of them here.