Among the dozens of beautiful, full-canopied oak trees lining Columbias Wateree Avenue, only one blew over in Wednesdays tree-toppling, limb-severing thunderstorm.
While the victim appeared to be a random choice, arborist Andy Boone of Dendrodiagnostics says the difference between staying upright and smashing down usually boils down to architecture. The majority of dozens of trees or large limbs that smashed down in Wednesdays storm likely were victims of hard-to-notice rot or mistreatment of their root system.
A tree can seem in good health, but if its architecture isnt in good shape, it can come down, Boone said.
Lots of them came down Wednesday, as strong winds associated with a thunderstorm toppled trees and snapped large branches in the older Columbia neighborhoods. City crews spend all day Thursday clearing trees off roads. Unlucky homeowners spent the day watching private crews hired by insurance companies cut trees off houses.
Most of those trees had some problem before Wednesdays storm, Boone said.
Tree rot usually begins when water collects in the crevices where a trunk separates into multiple trunks or where large limbs branch off. Trees grow around the rot, so its difficult to see ... until exposed when a section of the tree blows off at that rot-weakened spot.
Root damage can be caused by installing sidewalks or driveways over root fields or by cutting through roots while installing irrigation systems, Boone said. Cutting through roots or inhibiting their growth makes it harder for the root system to hold onto the ground when wind is bending the tree canopy.
Tree professionals can use probes to check the health of root fields and small-bore drills to check for rot, but its more common for the problems to be revealed by strong winds.
Recent heavy rains likely contributed to the damage in Columbia on Wednesday because saturated soil doesnt hold the roots as well as dry soil. But the compact root balls pulled up by many large trees Wednesday indicate their roots also might not have fanned out to healthy lengths. (Large trees root field can be two to four times the circumference of the tree canopy.)
The strong winds (a gust measured 56 mph at Columbia Metropolitan Airport) hit hardest in the Shandon, Old Shandon, Heathwood, Hollywood, Rose Hill, Rosewood and Wheeler Hill neighborhoods. The city documented slightly more than 100 locations where either entire trees were toppled or significant limbs fell, according to Missy Gentry, assistant city manager for operations.
Fewer than 100 homes were without power in Richland County on Thursday afternoon, according to SCE&G. Power outages were more of a problem in the Upstate, where nearly 5,000 homes still were without power in Greenville and Spartanburg late Thursday.
Some city workers said they worked until 1 a.m. Thursday, went home for a short break, and were back at work at 8 a.m. At the corner of Saluda and Seneca avenues, workers first trimmed enough small limbs to allow traffic to pass on Seneca. Then they took on the two tree trunks, probably 14 feet in circumference, that had fallen across Saluda.
One of those trees was a massive oak in the corner of Susan Thorpes front yard. It fell away from her house and even managed to spare a tiny lantana bush near its trunk. Thorpe and her husband heard it fall.
Weve lived here long enough to know, she said. Theres a certain sound you hear in a storm. We knew it was a tree. We didnt know it was two trees.
Another large oak in their neighbors yard also toppled across the road. Fortunately, Saluda is very wide at that point, and the trees didnt damage homes across the street.
Several thousand Richland County residents lost power during the storm, and a few dozen went without until mid-morning. The storm damage will have an impact well beyond the power outages and the holes in roofs.
Its heart-breaking, said Phyllis Trippe, who was in her Wateree Avenue home during the storm but didnt hear the large oak partially in her yard fall against her neighbors house. Its going to change the landscape. The trees are what everybody loves about this street. We were all out here almost crying when we saw it.
The tree appeared to be resting on her neighbors house without doing much damage. Cutting it off the house was going to be a tricky chore.
Many of the large trees in Columbias older neighborhoods are near the end of their normal lifespan, and those with the worst rot or root problems will be culled with each new wind storm, Boone said.
I dont want to scare people into cutting down all the trees, Boone said. People want to have trees. You have to accept some risk unless you want to live in a pasture.