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Sally Cunnignham: Do your homework before planting a tree

A friend lost an ancient cherry tree in a prominent location near his house and was going to transplant a wild one from his woods. “No, no!” I said. Yes, doing so sounds both economical and nature-friendly; we love our native trees. Many Prunus (cherries and plums) are in the woods. So, why not?

Answer: Because acquiring an important landscape plant, especially a large tree, deserves a thoughtful selection process; you’re starting a long-term relationship. Because the trees that were planted there half a century ago are not necessarily the best choice now for many reasons. Wild cherry and plum trees commonly suffer many disease and insect problems – not low-maintenance at all. (A fungus disease called Black Knot of plums and cherries typically spreads from wild Prunus trees.)

And, unless you really know the plants, you could be adopting a non-native, invasive plant. Our woods are loaded with Norway maples, Japanese honeysuckles, Russian olives and other possibly attractive plants that we should not be encouraging.

Bottom line: Take time to match the tree to your site and consider the less-known but wonderful choices your nursery professional has waiting in the field or on the drip line. Someone is watering your tree as you read this.

How to choose

You cannot judge a tree by what you see in the nursery. Those trees are in an unnatural situation, with limited root balls and somewhat stressed. They can’t tell you what they’ll be like in your yard. Work with a professional who will help you consider factors, such as:

• Solid shade or dappled? Wide or narrow shade coverage? Oaks, horse chestnuts and sugar maples will shade your yard or patio completely, but if you want some flowers or shrubs nearby, you’d do better with an airier tree canopy. Or choose a columnar shape that shades a limited area.

• Root competition and compatibility: If you or your neighbors ever plan to grow a tomato (or myriad other plants), a beautiful black walnut would not be a good choice. The roots have an alelopathic effect – prevent other plants from thriving. Many trees, notoriously maples, have extremely shallow roots systems that make nearby gardening nearly impossible.

• Messiness: While we and the birds adore crabapples and mulberries, place them where the fruits won’t clutter the sidewalk or stain the deck. Some trees break easily and drop twigs and limbs (silver maples, Chinese elms); avoid them near a house.

• Seasons of attractiveness: There are one-season knock-outs (magnolias, cherries) and four-season beauties (stewartias, katsuratrees) and many in between. For a prominent position choose something with more than spring flowers. Analyze foliage prettiness, fall color, silhouette and branch structure, wildlife benefit and the look of the bark in winter.

• Longevity, speed of growth, common diseases or insects: Don’t ask for trouble; ask what typically happens to this tree over time and weigh those factors for you.

Less-known candidates

• Betula nigra (River birch) and cultivars: Native birches belong in moist, acidic soil, but many tolerate yard conditions and suit Western New York landscapes – both single and multistemmed; great borer resistance. For example, the cultivar ‘Renaissance Reflection’ has white, peeling bark and yellow fall color (35 feet); ‘Heritage’ has cinnamon-colored peeling bark (50 feet).

• Carpinus caroliniana (American Hornbeam): Native, prefers some shade, at least 25 feet tall and wide; good fall colors; called Musclewood for its sinuous musclelike bark.

• Cerciiphyllum japonicum (Katsuratree): American plant guru Michael Dirr wrote that this is the one tree he would take to heaven if he were forced to choose, for its heart-shaped leaves (blue-toned to apricot in fall), gorgeous branching structure, lovely rounded shape (pyramidal when young) and dramatic shaggy bark when mature. Trouble-free; fast growing to at least 40 by 30 feet.

• Gingko biloba: Has thrived on earth for 150 million years; tolerant of many conditions; grows 60 feet upward and very wide; loved for leaf shape (the inspiration for many pieces of jewelry) and fall color (bright yellow); trouble free. Choose a male because the female’s fruit is stinky. Many cultivars exist, including a true dwarf and columnar choices.

• Gymnocladus dioicus (Kentucky Coffeetree): Once I saw an allée of these in the Nanem Arboretum in Ellicottville, I was hooked. If you can use a 60-by-40-foot tree, this is it. Features leathery 10-inch seed pods, scaly-patterned bark and dramatic silhouette; no problems and tough as nails (native as far north as West Virginia; hardy to zone 3).

• Maackia amurensis (Amur Maackia): Really hardy, tough, round, non-fussy, handsome tree, ultimately about 30 feet tall, with curling amber-brown bark when mature. Likes sun; potentially good street tree; thrives even in Minnesota (or frigid native habitat in Manchuria). Rarely seen.

• Metasequoia (Dawn Redwood): This deciduous conifer has soft needles that turn bronze or rust-colored before they drop in autumn, exfoliating bark and an interesting fluted base of the trunk. It’s extremely hardy and fast-growing (to 75 feet or more; only 25 feet wide); stunning gold-leaved or weeping cultivars available. It casts a gentle shade.

• Ostrya virginiana (American Hophornbeam, also called Ironwood): Native, 25 to 40 feet, less wide than tall; graceful, trouble-free and handsome.

• Oxydendrum arboretum (Sourwood): Native tree for four seasons, potentially a fine specimen, with fragrant, drooping white flowers, lovely leaves and fall colors, pyramidal shape. Likes full sun; needs acidic soil; doesn’t tolerate urban pollution; from 30 feet upwards.

• Stewartia pseudocamellia (Japanese Stewartia): This one captures my heart – beautiful even in a pot in a nursery – for its branching pattern and shape, and camellia-like flowers in July. Grows 25 to 30 feet typically and less wide; bark multitoned and shaggy with age; leaves turning yellow, red or purplish colors in fall. Prefers acidic soil and some afternoon shade.

Choose, plant and tend a shade tree with full knowledge. (Yes, you can begin the relationship even in high summer, as long as you know how to plant and water correctly.) A tree can be a wonderful companion for a lifetime.

Sally Cunningham is a garden writer, lecturer and consultant.