Central Ohio drought: How to save your trees and shrubs
COLUMBUS, Ohio (WCMH) — Central Ohio is in the grip of a stubborn drought, putting homeowners in the challenging position of trying to conserve water while keeping their trees and shrubs from suffering permanent damage.
Evan Floyd-Watson, general manager at Kevin Masters Arborist Services, recently shared expert advice on how people can keep trees and plants alive with timely and efficient watering. Floyd-Watson explained that excessive dry patches can “shrink” a tree's root system, leaving even mature trees unable to recover. When rain finally returns, there are fewer roots to absorb the water and the canopy will not get the support it needs.
“All of the roots need to get wet, not just the base of a tree,” said Floyd-Watson. “If you have a medium- to large-sized tree, don’t underestimate the extent of the root system.”
Many people assume their sprinkler systems or quick hose sessions are doing the trick, but often the water is not reaching where it is needed most. Floyd-Watson notes that “trees don’t care about property lines,” and advises people to seek their neighbors' consent to expand the perimeter of their tree irrigation efforts.
Floyd-Watson's best advice for making the most of watering is to “mimic the rain.” Watering in the cool of the morning or evening allows moisture to sink into the soil rather than evaporate in the heat. Midday sprinkling wastes water, with much of it lost to the sun. If homeowners find themselves limited to watering in the late afternoon, it is best to keep the water off the leaves.
“The important part is that it can’t wait,” said Floyd-Watson. “Root death may begin as soon as there’s no available water in the pores of the soil.”
According to Floyd-Watson, this summer’s dry spell has already erased much of the benefit from the wet spring. Big trees can mask their stress at first, with signs of drought damage appearing later.
“Typically, the larger the tree, the 'slower' the physiology,” said Floyd-Watson. “Root damage may be reflected in the canopy even years later with larger trees. One of the first signs is that leaves start falling, because trees protect themselves from losing water every morning by having less leaves.”
Even partial watering, however, can help them survive until conditions improve.
“Trees are like big straws, if you will, they open tiny holes in their leaves called stomata, every day, to release water vapor, which creates a suction-like process called transpiration. This is how trees and shrubs and other plants 'pull' water and minerals up from the soil.”
Additionally, Floyd-Watson said that different types of plants have varying needs during a drought, some showing stress more quickly than others. Smaller ornamentals such as rhododendrons, dogwoods, and taxus typically require watering once or twice a week. Larger shade trees like silver maples or oaks require more water than most homeowners can reasonably provide, but even occasional soaking can make the difference between survival and decline.
Some species have a more dramatic reaction to dry conditions. Buckeyes often drop leaves early as a defense against heat and drought. Birches tend to be sensitive as well, showing stress quickly. Japanese maples are prone to leaf scorch, especially on the south or west sides where they face the afternoon sun. This exposure can cause lasting damage that remains visible for the rest of the season.
Floyd-Watson said that while fertilizer, pruning, and soil treatments may all play a role in plant health, none can replace a steady supply of water when conditions turn this dry.
“They say, an ounce of prevention is worth a pound of cure,” said Floyd-Watson. “We can bring a struggling and drought-stricken tree back from the edge of death, maybe, but it’s a lot more predictable to just keep it watered.”