Park & Pilgrimage Information
Air Pollution is Blurring Park Views
Air pollution, usually considered a city problem, is mucking up scenic views in the wilds of the Great Smoky Mountains.
Whereas 50 years ago a vacationer perched at Newfound Gap could see an average of 113 miles, today he or she can see only 25. In summer, a season that once ranked among the clearest, the average view is now only 14 miles.
Scientists studying air pollution trace our shrinking views to small particles, mostly sulfates, produced by the burning of coal. Because these particles reflect and scatter light, we see a whitish haze rather than views of distant mountains. Coal-burning power plants and factories are the main contributors to this type of pollution.
Sulfates and other air pollutants travel to the Smokies on rivers of air from as far away as the Midwest, Gulf Coast, and Northeast. The mountains and predominant weather patterns then trap and concentrate the pollution in and around the park.
The National Park Service is involved in a number of projects aimed at reducing air pollution in the Smokies. Most importantly, for over 20 years the park service has continuously monitored visibility and other types of air pollution. Through these efforts the park service has been able to identify types and sources of air pollution impacting the Smokies.
Park officials are using this information to help inform legislators and promote initiatives to improve air quality. As a result, some power companies have been persuaded to retrofit old plants with advanced scrubbers and other pollution control devices. Tougher standards and improved technologies will significantly reduce emissions from several large power plants over the next few years.
However, increasing demand for electricity in the East and Midwest continues to threaten air quality. Dozens of new power plants that would affect air pollution in the park have been proposed. If views in the Smokies are to improve, we will need to control existing sources of pollution and address the cumulative effects of new ones. You can help:
- use energy efficient appliances, vehicles, and lawn maintenance equipment
- don’t waste electricity in your home or gasoline in your car.
Hemlock Woolly Adelgid
Eastern hemlock, one of the most common trees in the Great Smoky Mountains, is under attack from the Asian hemlock woolly adelgid (HWA). This tiny, non-native aphid-like insect has been seen in most parts of the park, including on some of the massive old-growth hemlocks that may be 500 years old. No hemlock deaths have been recorded yet, but many trees show crown damage already.
HWA is the second adelgid to sweep through the park; in the 1960s the balsam wooly adelgid infested higher elevations, killing most of the mature Fraser firs. On Clingmans Dome, visitors gasp at the sight of fir skeletons dominating the views. It is hard to imagine what the park would look like without the hemlocks lining the creeks and climbing the hillsides. Ecologists cannot predict which species could replace hemlocks, which dominate many habitats in the park. Many birds, insects, and other animals depend of hemlocks for food and shelter.
The possible effects of destruction of hemlocks has been compared to the death of American chestnuts. But there’s one big difference: Park scientists and staff are prepared this time. They first saw HWA in the park last year, and they have already started aggressive management procedures. One of the most interesting is the introduction of tiny beetles that make a living eating HWA. Preliminary results show that beetles released in a few areas reduce the severity of the adelgid infestations. However, it is time consuming and expensive to raise the beetles, and vast areas need to be treated.
Federal funding may be available soon to set up a beetle rearing facility, but in the meantime, Friends of the Smokies and Great Smoky Mountains Association are bridging the time gap by providing money to set up a lab at UT to release beetles over a year earlier. The beetle rearing facility in the new biotech building on UT’s Agriculture Campus will have walk-in incubating rooms with large growth chambers. Technicians will collect infested hemlock branches to feed the hungry HWA larvae.
Research is currently underway to evaluate the biology of the beetle and what effect a widespread release will have. The beetles apparently eat only HWA; it is hoped that their populations will fluctuate with the adelgid so that the hemlocks can withstand the infestations over time. Beetles may be released as eggs, larvae, or adults; research will help determine the best life stage.
Other control strategies include spraying trees with insecticidal soap, which is only feasible near roads, and injecting an insecticide into tree roots. The beetle release, if successful, has the great advantage of distributing these tiny predators throughout the park and continuing to work as adelgids reinfest the park from surrounding areas.
A special Save the Hemlocks T-shirt has recently been developed with all proceeds going to the effort. To help save the hemlocks, go to http://www.friendsofthesmokies.org or call 1-888-898-9102 to order your Save the Hemlocks T-shirt.
Smoky Mountain Elevations
Clingmans Dome 6,643 feet
Mount Guyot 6,621 feet
Mount Le Conte (High Top) 6,593 feet
Mount Buckley 6,580 feet
Mount Love 6,420 feet
Mount Chapman 6,417 feet
Old Black 6,370 feet
Luftee Knob 6,234 feet
Mount Kephart 6,217 feet
Mount Collins 6,188 feet
Andrews Bald 5,920 feet
Charlies Bunion 5,565 feet
Newfound Gap 5,046 feet
Alum Cave Bluffs 4,970 feet
Spence Field 4,920 feet
Chimney Tops 4,800 feet
Ramsey Cascades 4,300 feet
Cataloochee Valley 2,680 feet
Laurel Falls 2,600 feet
Oconaluftee Visitor Center 2,040 feet
Cades Cove Visitor Center 1,716 feet
Sugarlands Visitor Center 1,462 feet