All oaks aren’t ‘angels’: Water oaks as common as live oaks but not nearly as strong

By Helen Mitternight Special to The Post and Courier

Experts pegged the potential killer at anywhere between 175 and 300 years old and gorgeous – but rotten at the core.

If that seems dramatic, it’s because the killer – a massive water oak, 5 feet across and 14 feet around – was in my own backyard in downtown Charleston. As Charleston prepares to celebrate Arbor Day on Dec. 2, it pays to remember that ignorance is not bliss when it comes to these beauties.

Unlike live oaks, which live well into their hundreds, water oaks usually live only 70-80 years, according to Danny Burbage, Charleston’s assistant director of parks.

The trees can die from the inside out, which is why this tree still had full, healthy branches. Only after Hurricane Matthew did a split appear that you could see the sky through, and the city said the tree, more than 100 feet of potential killer, had to come down immediately.

“(Water oaks) hollow out in the middle. When you cut the tree down, water rushes out of the center,” says James Critikos, owner of The Tree Men in Mount Pleasant.

Charleston is known for beautiful spreading live oaks like the Angel Oak or the Middleton Oak. Burbage says live oaks have elliptical leaves, while water oaks can have several different shapes of leaves in the same tree, with the ones getting the most sun shaped like a kitchen spatula. He contrasts live oaks with their “alligator back” bark that has deep furrows and is dark brown or blackish with water oaks that are smoother with almost a gray color.

Another important difference is that water oaks tend to be more vertical with relatively shallow roots, while live oaks can spread 100 feet across. This horizontal orientation is what makes the live oaks better adapted to the kinds of winds Charleston sees in hurricanes like Matthew.

“Live oaks tend to be more open in the crown, so wind passes through them,” Burbage says. “Also, live oaks have a more resilient root system. The root tends to be more widespread so there is more of a support to keep the tree from toppling over. Live oaks also compartmentalize and seal off decay very well. Water oaks do not. Water oaks, when they get a decay process started, it tends to spread more readily and they get more root rot, which causes them to fall so much in high winds and rains.”

Tree protections

If you are thinking it might be a good idea to remove that water oak in your yard as a preventive, think again. Charleston takes its trees very seriously.

Burbage says that there are ordinances protecting trees. On single-family private property, a permit is required for any tree 24 inches or greater in diameter, and 8 inches in diameter on commercial or multiunit properties. The exception is pine or sweet gum trees.

“You can trim trees, you just can’t take them down or mutilate them without a permit,” Burbage says. “Except for pine trees and sweet gum trees. People got so afraid of pine trees after (Hurricane) Hugo and people think sweet gum just isn’t a good urban tree. I don’t necessarily agree with that.”

Trees on public property like sidewalks or parks are protected no matter what size or species.

Not only does Charleston protect its trees, it’s pretty familiar with how many it is protecting. Burbage says a census was done in 2000 after a 1991 federal grant enabled the city to hire people to do a tree inventory. The database stays updated and his department is in the midst of adding information with GPS coordinates for each tree.

The census is how Burbage can say that about 30 percent of Charleston’s trees are oaks and 75 percent of those is fairly evenly divided between water and live oaks.

The city will be celebrating all things tree on Dec. 2, South Carolina’s Arbor Day this year, with a celebration and tree plantings in the Maryville/Ashleyville neighborhood.

Burbage says trees are a good investment because, for every dollar spent on tree care on public lands, the city gets back $1.15 in energy management, energy savings, storm water runoff mitigation and property value.

If that kind of return on investment makes you want to plant your own tree, Burbage says oaks are a good bet if you’re careful about where you plant them.

Once a newly planted tree gets acclimated – Burbage says that takes nine months for every inch in the tree’s diameter – the growth can be rapid. Water oaks can grow 6 to 8 feet a year, and live oaks grow a couple of feet a year.

Risky business

As for the potential killer in my back yard?

It came down. The process took four days and a lot of stress. The tree removal company noted that the limbs were large and full and were held aloft by a delicate, rotted trunk, making it top-heavy and extremely dangerous, as well as impossible to put a person in the tree to saw off limbs.

“I thought it was really dangerous with the risk of breaking before the tree removal person is finished making the cut,” says Ary Fun of Ary Fun Tree Services in Charleston. Fun often works with Burbage on hazardous tree removal and was bought in to consult on our tree. “It can break 15 to 20 feet above the cutter on the ground and then he doesn’t have enough time to react and run far away.”

Instead, Fun recommended putting someone in a lift next to the tree and making the cut 40-50 feet up, where the trunk was a bit more solid so the direction of the fall could be controlled.

“That tree was ridiculous, unbelievable,” Critikos said. “But that tree had a heck of a life.”