Smoky Mountain Hemlock Trees

Smoky Mountain Hemlock Trees are receiving a lifeline.

Smoky Mountain Hemlock trees are one of the most beautiful evergreens in GSMNP!

Horticulturists hope a new hybrid hemlock will prove resistant to the hemlock woolly adelgid which has decimated the broadleaf evergreens for more than 25 years.  

The majestic trees, which serve as green sentinels in the Great Smoky Mountains punctuating the summer mountains scenery with dark green foliage and offering a welcome contrast to leafless trees in the winter, have been slowly dying in the mountains for 25 years.

The culprit is the hemlock woolly adelgid, a small white fuzzy insect, which arrived from East Asia some 70 year ago and has spread widely during the past few decades. The pest feeds on the tree’s sugary sap. The tree’s defensives mechanism reacts to the feeding by shutting off affected areas and when enough infestation is present the tree literally goes into a death spiral.

Beloved by home landscapers for its large growth and attractive fine texture Hemlocks are one of the few evergreen conifers that does not crave sunlight. The tree lends itself to formal clipped hedges and provides structure and screening to home gardens.

The Hemlock Wooly Adelgid has decimated the forest up and down the east coast.
The Hemlock Wooly Adelgid has decimated the forest up and down the east coast.

According to a report, breeders at the Agricultural Research Service in Beltsville, Maryland have worked for almost 20 years to produce a cross between the Carolina Hemlock and the Chinese hemlock that is tolerant of the pest. Dubbed “Traveler,” the breeders think that nurseries will be interested in growing the tree and that it can reach consumers in a few years. The Traveler hybrid, from which all future clones will be made, has topped out at 30 feet with an 18-ft. girth in a little more than 15 years. Resembling a deodar cedar, the relatively slow growing hybrid, features lime-green cones and pendulous branch tips. 

The task has proved challenging said Margaret Pooler, the project’s research leader, who was quoted as saying that repeated efforts to cross the Chinese species with the eastern hemlock proved fruitless. She noted that there are very few Chinese hemlocks available. The mother tree to Traveler is a Chinese hemlock growing the U.S. National Arboretum and sourced from a Pennsylvania conifer arboretum in 1959 from trees originally brought from China. The second parent was from a now-dead Carolina hemlock found in the estate of plant explorer David Fairchild (1869-1954.

Hemlocks are wind-pollinated and tracking the thousands of seedlings, which require a DNA test to determine if they are hybrids, is difficult. The seedlings are also tested to determine growth habits and adelgid resistance. 

Although the research is promising for home landscapers it is not the solution for restoring native populations. The hybrid clonesn lack the genetic diversity needed in a wild population. There is, however, a glimmer of hope. Using cuttings from rare survivors in the wild, which have innate resistance to the pest plant, scientists at the University of Rhode Island are working to restore the native tree. According to Evan Preisser, a professor in the university’s biological science department, a four year trial in seven states determined that only 4% have died, compared with 52% of control specimens. 

The findings provide a strong argument for reforesting areas with resistant trees but it will take time, said Preisser who added that it took Asian species of hemlock some 100,000 years to evolve and build up a resistance to the adelgid. “We are trying to speed up that process,” he said.

This research provides hope for the iconic hemlocks.

More Hey Smokies Features:

Five Best Hikes To Mount LeConte
Five Best Hikes To Mount LeConte...
These hikes to Mount LeConte are worth the effort! Five best hikes to Mount LeConte. LeConte Lodge is the only overnight lodging, [Read More >>]
No thumbnail available
Laurel Falls Access Fee Proposed...
Laurel Falls Access Fee Proposed. Great Smoky Mountains National Park is seeking public input on the Laurel Falls Trail Congestion Manageme[Read More >>]
No thumbnail available
Smoky Mountain shuttle opportunities for Cades Cove Vehicle-Free Wednesdays...
Smoky Mountain shuttle opportunities for Cades Cove Vehicle-Free Wednesdays. Shuttles begin July 7, 2021 and will run through September 1, [Read More >>]
Smoky Mountain Bear Attack
Smoky Mountain Bear Attack...
Smoky Mountain bear attack! Smoky Mountain Bear Attack. Great Smoky Mountain National Park officials have closed backcountry campsite 29 in [Read More >>]
Smoky Mountain Strawberry Moon
Smoky Mountain Strawberry Moon...
Smoky Mountain Strawberry Moon is on the rise! Smoky Mountain Strawberry Moon is on the rise! This first full moon of summer 2021[Read More >>]
No thumbnail available
Hike Naked Day!...
Hike Naked Day! That is right, June 21st is the official international hike naked day! The free and easy event is often a rite of pass[Read More >>]
No thumbnail available
Smoky Mountain Cicadas...
Smoky Mountain Cicadas. What's all the buzz about? A rare natural history event is unfolding right now! This month through mid-July, bi[Read More >>]
No thumbnail available
Lights, Camera, Action! Appalachian Bear Rescue double your donation campaign!...
Lights, Camera, Action! Appalachian Bear Rescue double your donation campaign! Now's the chance to DOUBLE YOUR DONATION impact and give you[Read More >>]
Smoky Mountain Road Work Scheduled
Smoky Mountain Road Work Scheduled...
Smoky Mountain road closures set to snarl traffic. Smoky Mountain Road work Scheduled. Smoky Mountain road crews will close single north and[Read More >>]
Smoky Mountain Volunteer Opportunities
Smoky Mountain Volunteer Opportunities...
Smoky Mountain Volunteer Opportunities in May and June of 2021. Park staff are hosting several volunteer workdays on trails throughout the [Read More >>]
No thumbnail available
Abrams Falls Trail Rehabilitation Begins...
Abrams Falls Trail Rehabilitation Begins. National Park officials announced that a Trails Forever rehabilitation project in Cades Cove will[Read More >>]
Greenbrier Open To Public
Greenbrier Open To Public...
Greenbrier Open To Public. Great Smoky Mountains National Park rangers announced the Greenbrier area of GSMNP reopened to all pub[Read More >>]
Rainbow Falls Trail Closed for Bridge Replacement
Rainbow Falls Trail Closed for Bridge Replacement...
Rainbow Falls Trail Closed for Bridge Replacement.  Great Smoky Mountains National Park officials will temporarily close Rainbow Falls Trai[Read More >>]
Smoky Mountain Tamale Recipe
Smoky Mountain Tamale Recipe...
Smoky Mountain Tamale recipe. Homemade tamales are always a Smoky Mountain special event! Did you know that the Smoky Mountains are on the [Read More >>]
Great Smoky Mountain Synchronous Firefly Lottery
Great Smoky Mountain Synchronous Firefly Lottery...
Smoky Mountain synchronous firefly dates announced. Great Smoky Mountain Synchronous Firefly Lottery will begin Friday, April, 30 2021 at 10[Read More >>]
Smoky Mountain Interstate Wildlife Crossing
Smoky Mountain Interstate Wildlife Crossing...
The Pigeon River gorge interstate wildlife crossing will provide safe passage for bear, elk and their furry friends! Smoky Mountain Intersta[Read More >>]
Cades Cove Car Ban
Cades Cove Car Ban...
The Cades Cove car ban will allow walkers, runners and bikers an opportunity to enjoy the Cove without the congestion and noise of cars. Cad[Read More >>]
Great Smoky Mountains National Park Nudist Colony Bares All
Great Smoky Mountains National Park Nudist Colony Bares All...
Great Smoky Mountains National Park Nudist Colony Bares All. Great Smoky Mountain officials announce the grand opening of the new Cades Cov[Read More >>]
No thumbnail available
Smoky Mountain Earth Day Trash Pick Up...
Smoky Mountain Earth Day Trash Pick Up will be held on Earth Day, April 22, 2021. This year Earth day reminds us to take care of and apprec[Read More >>]
Smoky Mountain Bears
Smoky Mountain Bears...
Smoky Mountain Bears are the symbol of the Smokies and sighting one is always a special event! With the tourist season in full swing and a recor[Read More >>]