NANCY SZERLAG

Gardening: Think ahead before choosing, planting a tree

Nancy Szerlag
Special to The Detroit News

One of the most common questions asked on the late Jeff Ball’s website Yardener.com is, “What’s wrong with my tree?”

Yardeners tell me their trees’ leaves have turned brown, yellow or black. If one side of the tree is affected it may well be sun scorch. But when the condition runs throughout the entire canopy, the cause may be some other environmental issue or a disease. Too little or too much water will turn the edges of tree leaves crispy brown. Leaves crumpled and curled or covered with lumps and bumps or spot and dots may be diseased or suffering an insect attack – or both. Leaves that have been chewed upon or lasered to lace are the targets of insects and if the tree’s new growth and flowers are gone, chances are Bambi and her mom stopped by for a snack.

Some problems are obvious, but most are not and I am not a trained tree doctor, so my best guess is just that, a guess. And, my pat answer for most tree problems is to get an onsite inspection from a certified arborist. To find one in your area go to tcia.org.

In an article in the Michigan Landscape, a publication of the Michigan Nursery and Landscape Association, Dr. Bert Cregg, associate professor of Horticulture and Forestry at Michigan State University, discussed what to consider when choosing and siting a tree with drought conditions in mind.

Trees planted close to large expenses of hardscape such as light or white walls, sidewalks, driveways or patios may suffer from refracted heat load as well as well as ambient temperatures. Damage to foundations and cement and brickwork may require the removal of roots that may compromise the health of a tree.

Scientists tell us drought-like conditions may be the new normal and since moisture is the life’s blood of a tree, we should take that into consideration when choosing trees.

Bert Cregg explains that some trees have adapted to dry conditions and are more tolerant of drought than others. Thicker leaves, smaller leaf surface, deeper rooting patterns, and more extensive rooting patterns are some of the adaptations.

Trees that are relatively tolerant of drought include Bur Oak, Honey Locust, Hickory, Hackberry, Gingko, Walnut, Sassafras and Elms.

Trees that are intolerant of drought according to Cregg are Katsura, Tulip poplar, Willows, Hemlock, Firs, Sugar Maple, Horse chestnut, Japanese Maple and River Birch.

Cregg notes that these lists are not all-inclusive, but intended to provide examples of common trees in each category.

Nancy Szerlag is a master gardener and Metro Detroit freelance writer. Her column appears Fridays in Homestyle. To ask her a question go to Yardener.com and click on Ask Nancy. You can also read her previous columns at detroitnews.com/homestyle.