LITTLE ROCK — When Patti Erwin drove from Fayetteville to Little Rock last month, she looked at the trees.

She saw:

“On the ridges where there’s little soil, the trees have turned brown.”

She saw:

“In 2009 we had that ice storm in the north half of the state, and a lot of tree branches were cracked.

We’re seeing those cracked tree branches dying because they can’t push the water through.”

She saw:

“Certain species on the interstate are being [affected]. It almost looks like fall. Some trees have already turned yellow. That’s how they deal with the drought, by going dormant.”

Erwin’s an urban forester for the Arkansas Forestry Commission.

“I’m worried,” she said, about those trees.

No wonder. More than half the state has experienced an exceptional drought, the worst category, this summer, according to the national Drought Mitigation Center in Nebraska. A map of the state would show the exceptional drought in a rough triangle from Benton County in the northwest to Sevier County in the southwest to Clay County in the northeast.

SAVE THOSE TREES!

While farmers worry about crops, homeowners - and foresters - worry about the trees.

Homeowners can do a lot for their trees, Erwin said.

Water. Roots are in the top 12-18 inches of soil. Water thoroughly at night. “The feeder roots will get a lot of that.”

Smaller trees can be watered with a 20-gallon water bag.

If the drought continues, water in the winter.

Mulch - even big trees. Mulch keeps the soil around trees moist and cool. Use shredded wood mulch but don’t put it up against the trunk.

Vic Ford is director and professor at the Southwest Research and Extension Center at Hope, part of the University of Arkansas System Division of Agriculture. He has been the director since 2008.

The center has 1,200 acres on which research is done on beef cattle, forage, and trees. There’s even a nematode diagnostic laboratory, a nematode being a microscopic roundworm that’s a parasite to tomatoes, cotton and trees.

Forestry research there dates to 1927, Ford said. Natural stands of native hardwood have been under management since 1947. Those hardwood plantations include, among other trees, sycamore, sweetgum, oak and cypress.

WHAT TO PLANT?

Ford recommends the Nuttall oak for home landscapes.

“It’s a remarkably adaptable tree,” he said. “It grows in a wide range of soil acidity and nutrient content.”

Available at nurseries, he said, the Nuttall oak’s branches “are rather small compared to other oaks. They have fine branches, comparatively. They have a decent growth rate and are good for an urban environment. The Nuttall has a pyramidal crown. You don’t get a brushy tree hanging over the house. And it has a nice compact form that’s pleasing to the eye.”

Trees of Arkansas, published by the Arkansas Forestry Commission, says the Nuttall has other, local, names - Texas oak and striped oak. It grows to 70-120 feet with a conical crown, is used as shade tree and for lumber, and is “one of the most common and useful trees of the bottoms,” the book says.

WHAT NOT TO PLANT?

Ford’s first piece of advice to homeowners is this:

“Bradford pears are not a good choice anytime. People like them, but they’re shortlived and very brittle. Windstorms break them up - I moved into a house with two, and have one left.”

People like Bradford pears because they flower, have a nice shape, have a rounded crown and attractive fall colors,Ford said.

“But they’re an invasive species, an exotic - not native - tree. We’re starting to see them cropping up in the wild, like kudzu, interfering with our native vegetation.”

STUDY THE SOIL

Ford’s second piece of advice to homeowners: “Know what kind of soil you have. Take some of your soil to your county extension office. Know the pH in your yard. That way you can narrow down the choices to what will grow.”

Pine, hickory or oak do well in a low pH, or acid, soil. Ash or crab apple do better in a high pH, or alkaline, soil.

WATCH THE ROOTS

“Now here is the best piece of advice I can give landowners: Large trees have large roots,” Ford said.

Work around the house or in the yard can disrupt the roots “and create a significant risk in distressing that tree in dry periods. You end up with the favorite large tree you bought the house for, it dies because of a project. Disturbing the root system is not a good thing.”

ADAPTABILITY COUNTS

A tree should be adaptable to the site it’s planted on, Ford said, with room for the roots to grow. It should be vigorous, able to resist insects and diseases. How to know these things?Get a copy of Trees of Arkansas, for starters, and pay attention to the planting instructions on the label of a tree bought at a nursery.

“Everybody loves dogwoods, but they are shade adapted, much better in shade than open sun,” Ford said. “They take a long time to build up a root system. They’ve got to have a little bit of shade.

Erwin says homeowners have lots of choices of native trees and should plant according to the hardiness zone in which they live. For instance, she said, from Little Rock south, sugar maples are a poor choice. Everyone wants the beauty of the sugar maple in the fall, but it doesn’t do well in warmer zones.

Hickories, though, are a good urban tree, with naturally smaller canopies for smaller yards.

A non-native tree suited to an urban environment is the Chinese pistache, a small shade tree that grows to about 35 feet in height and has brilliant fall foliage that varies from clear yellow to scarlet.

The ginkgo, which turns a golden yellow in the fall is also good in an urban environment. “They’ve been around forever,” Erwin said. A caution from Trees of Arkansas: The male ginkgo is “very satisfactory as a yard tree,” but the female ginkgo “produces a fruit with a putrid odor that makes it less desirable.”

Whatever tree a homeowner chooses, Ford said, “match the soil, the area to cover, and the growing conditions.”

HomeStyle, Pages 39 on 09/01/2012