Tree health vulnerable during drought

Sounds of crickets and wildlife and the mountain view off Lake Chatuge served as a relaxing release for the volunteers at the United Methodist Missions Center at the end of a long work day.

Situated in the town of Hayesville in Western North Carolina, the missions center welcomed volunteers in the summer to devote their time and labor with help from staff members like Brittany Johnson, a junior in biomedical engineering.

But as volunteers from years past returned to the center, they noticed something different -- Lake Chatuge was slowly getting more shallow as the summer drought took its toll.

As water restrictions tighten and water levels drop farther, the green colors of the maples, oaks and beeches the volunteers at the center enjoyed over the summer will fade to brown before changing to their fiery oranges and yellows, according to associate professor of forestry Robert Bardon.

"In nondrought conditions, leaves naturally change color because the green pigment of the chlorophyll fades and allows the other colors of the spectrum to show," Bardon said. "During a drought, trees tend to go dormant in an effort to conserve carbohydrates that are needed for survival and the protection against disease."

According to Bardon, trees are especially susceptible to droughts because they require hundreds of gallons of water to stay replenished. Without the necessary amount of water over a period of time, root systems dry up and trees go through a self-preservation process that results in the loss of the aesthetically pleasing colors of the leaves.

Early dormancy also takes away from a tree's photosynthesis process -- a major factor in the health of a tree and its rate of survival in the coming years.

"Besides the loss of aesthetic value, humans will notice a smaller growth rate in trees, among other factors that come from high levels of stress on a tree," Bardon said.

One of the biggest concerns among tree specialists is the threat of disease to trees under stress. Like humans, high stress levels can lead to lower immunity, resulting in a higher occurrence of everyday diseases. Fungi and insects like the southern pine beetle can potentially harm and result in the death of a tree in the coming months. Johnson said that as the summer continued, the rain returned, sometimes for days at a time -- something Bardon, who also works as a forestry extension specialist, hopes will keep the trees healthy in the coming years.

"There is a chance that if we receive more water in the coming months than normal, that the trees most affected by the drought will have a higher survival rate, but we won't know for almost a year," Bardon said.

In the meantime, mulch is the most effective way to protect trees at home from succumbing to the effects of the drought, according to Bardon. He said it was important to mulch each tree to the edge of the shade provided by its branches, a point called the crown line. The crown line can reach anywhere from 15 to 50 feet from the trunk of a tree.

"By providing a thick layer of mulch around the base of a tree, key nutrients and water are kept closer to the root system closest to the trunk of the tree, therefore protecting the trees we enjoy so much," Bardon said.