Zombies are in your yard, in parks and along roadsides and other green spaces throughout Texas.
They’re trees that are partly dead and partly alive, struggling to move forward and waiting for the next big thing — even hotter temperatures, a drought, a hurricane — to seal their fate.
Count zombie trees as one more lingering effect of February’s winter storm.
Arborists and other tree experts say that in the months to come, the state could lose thousands if not millions of trees ranging from tall Mexican or California fan palms to a wide range of hardwoods such as lace bark elm, Chinese tallow and water oak. This would be the most dangerous threat to Texas’s tree inventory since the 2011 drought.
Trees with lots of dead branches and new green sprouts shooting out of the center are likely zombie trees. Even tall palms with new green fronds on top could be zombies, because you can’t see the potential damage inside of their lanky trunks.
Matt Petty, assistant district manager and a certified arborist at the Davey Tree Expert Co., said that the International Society of Arboriculture is calling for a two-year watch on trees damaged in the freeze.
“The zombie tree concept comes from trees that, from a distance, appear to be normal or healthy and as you get closer, you see the differences. They’re dead and we don’t know it yet,” Petty said, noting that the trees could have been struggling before the freeze. “Trees that lost their leaves from the freeze have sprouted out and, in many cases, look like they have recovered. As temperatures heat up, though, we’ll have trees that die.”
Petty said that he’s seen sycamores, rain trees, Chinese tallow, elms and water oaks suffering damage, but live oaks and magnolia trees — both popular shade trees in the Houston area — are doing well.
David N. Appel, a Texas A&M professor and a specialist in tree pathology noted that “zombie tree” isn’t a horticultural or agricultural term and showed restraint in using it.
He said that most trees with dead-looking branches and new shoots coming from the center could be zombie trees, but not all are. They’re certainly damaged trees, some of which will live and some of which will die, and it’s fairly obvious which branches should be pruned back.
“I’ve been from the Rio Grande all the way up to Wichita Falls, and I have talked to a lot of arborists and one thing is clear: The damage was remarkably similar, it’s just that the species were different depending on where you are,” Appel said. “In one place you hear a lot about lace bark elms, but in another place it might be some of the oak species. In Wichita Falls it was the Japanese black pine and Mondell pine.”
Appel said Texas will lose hundreds of thousands, possibly millions, of trees.
“The picture has become much clearer than it was two months ago, but we still (won’t know the fate of) a lot of these trees for a long while,” he said. “We aren’t out of the woods yet, and that’s not a tree joke.”
The story references the 2011 drought, which was hell on trees in Houston and around the state, and Hurricane Harvey, neither of which is a great comparison for arborial life. Some trees, like palms, were recognizably dead following the February freeze, but for others it may not be certain for another year or two. For those of us who live in neighborhoods with older trees, it is worth the time and expense to have an arborist look at the trees around your house, because dead branches are a real threat in a big storm. Hope for the best, and do what you can to take care of the trees on your property.