Serving Boone, Blowing Rock, Banner Elk, and other towns of the North Carolina High Country | Founded 05-05-05

The Power of Being Proactive—Hope For Grandfather Mountain’s Hemlocks

Story by Sam Calhoun

Catherine Morton, marketing director for Grandfather Mountain, remembers her father Hugh Morton often speaking of how beautiful the American chestnut trees were when he was a child. The late Hugh Morton—conservationist, photographer and owner of Grandfather Mountain—told his kids that one out of every three trees in the High Country forests was an American chestnut when he was young.

However, the American chestnut blight destroyed all those trees in the early twentieth century, so when news of the hemlock wooly adelgid (HWA)—a tiny insect that is killing hemlocks up and down the East Coast—infestation hit the East Coast in the 1990s, Hugh Morton didn’t hesitate to act.

The HWA infestation is potentially even more devastating than the chestnut blight, and efforts so far to arrest its spread and its deadly infestation of indigenous hemlocks have failed—to an extent.

Many local landowners and conservationists have used the last decade to fight the HWA with various methods, from chemical to biological, including Grandfather Mountain. Thanks to Hugh Morton’s foresight, the mountain started treating its hemlocks in 2004.

The result gives hope to a fight that seems all but lost when observing the broad swath of dead hemlocks now in the High Country. Of the more than 1,200 hemlocks that Grandfather Mountain’s employees have treated since 2004, 85 percent remain undamaged.

Catherine Morton said that before the first HWA was spotted in Watauga County, Hugh Morton committed the full resources of the Grandfather Mountain company to saving the mountain’s hemlocks.

Grandfather Mountain’s campaign against the HWA started by surveying the property to identify how many hemlocks are on the mountain and where. Trail rangers Kyle Woosnan and Jesse Cole, naturalist Jesse Pope and ASU graduate student James Graham walked the property to locate and map trees. The crew eventually identified more than 1,200 hemlocks visible from the summit road, from the trails that crisscross Grandfather’s wilderness backcountry or from other points of the mountain.

In 2004, the crew started spraying the trees closest to the road with chemicals. Spraying the trees, according to Pope, is the most effective and least costly method. Also in 2004, the crew started using tree IVs—a system in which chemicals, stored under high pressure, are shot into the tree using needles placed at various points—to kill the HWA. Tree IVs proved to be expensive and slow, but the crew kept working to keep the trees on life support while the HWA continued to spread.

At the end of 2004, the crew began using Mauget applicators—small, pressurized, chemical-filled pills that are inserted into drilled holes in the hemlocks. The capsules worked well, according to Pope, but the crew needed a way to work faster and more efficiently if they wanted to save a majority of the trees.
This fall, the crew at Grandfather Mountain is switching its attack method to soil injections of imidacloprid, a drug made by Bayer that has proven to be most effective in combating the HWA but carries with it a connection to the decline of honeybees across the nation. Knowing the dangers of imidacloprid if it spreads beyond the hemlocks it is working to save, the crew at Grandfather Mountain initially decided against using the chemical. This year, scientists invented a stopping agent for the chemical that allows the chemical to bond with the soil and not run off into nearby streams or infect nearby wildlife, flora and fauna.

“Now it’s more effective and less environmentally damaging,” said Pope. “The process is cheaper, it can treat more trees and it takes less equipment to do it.”

“When we were first developing our strategy for saving Grandfather’s hemlocks, naturalists chose not to use soil injections because they thought, with our thin rocky soils and steep grades, the chemical might run off into our streams,” said Catherine Morton. “The industry has since come out with a stopping agent that is added to the mixture to keep the chemical from moving around in the soil. It bonds with the soils around the injection site and pools the chemical around the root crown.”

Grandfather’s rangers treat each of the more than 1,200 hemlocks every other year, treating in-park trees one year and backcountry trees the next.

Because of Grandfather Mountain’s success, the Blue Ridge Parkway is starting to use soil injections as well this year.

“With systemic injections, our rangers think we can treat around 50 trees per day. The Parkway says they can treat over 100 trees in a day with soil injections. We are interested to see if we can up our efficiency as well because allocation of staff time is a limiting factor,” said Catherine Morton. “We’re committed to the fight, though.”

Whereas Grandfather Mountain is seeing success in the fight against the HWA, it comes with a price tag. In the fall 2004 Grandfather Mountain newsletter, Grandfather Mountain Vice President Harris Prevost wrote “We plan on injecting and spraying for as long as it takes. We’ll spend whatever we have to spend to save as many hemlocks as we can.”

Although the price was slightly higher in the first years, Pope estimates that it costs Grandfather Mountain around $15,000 per year now to continue the treatments.

Catherine Morton said that in the beginning when the HWA was a new concept to North Carolina, commercial companies cut Grandfather Mountain a break, price-wise, on equipment. When that grace period ended, though, the prices went up. Thankfully, the price of imidacloprid went down in recent years, according to Pope, because the patent on the chemical ran out and prices dropped accordingly.
“The battle is still very much going on,” said Pope.

Pope is happy, though, because he is finally seeing the results of the treatments. Treated hemlocks across the mountain look alive, healthy and lush and feature new growth and thick canopies, he said, whereas the untreated hemlocks feature a gray cast, 60 percent of their needles are gone and some are even completely dead.

“My long-term hope is that bio-controls can take hold,” said Pope, who released predatory beetles on a portion of the mountain to see if they could combat the HWA in unreachable territory. “I think that’s still the long-term solution—the work that Dr. Richard McDonald is doing in this area with the beetles. In the short term, it’s just trying to keep our trees alive in the meantime—it’s like they are on life support.”