The Brooklyn Botanic Garden, home to 52 acres of plants including some of the city's most prized specimen trees, reopened less than a week after Hurricane Sandy swept through New York recently. What enabled the garden to recover so quickly? Routine tree care. Make that excellent routine tree care. The same strategy will work on your trees:
Photographs courtesy of Brooklyn Botanic Garden.
Above: After the storm, arborists fanned out to identify and remove damaged limbs. A good tree maintenance program focuses on three things: root care, soil protection, and regular pruning. "There's a strong correlation between the visible, top part of the tree and what's going on below the ground," says Melanie Sifton, the garden's vice president of horticulture. "The first rule is to protect the root zone." Photograph by Elizabeth Peters.
Most trees have relatively shallow roots that grow outward from the trunk, to a diameter two or three times larger than that covered by the crown of the tree. "People think of trees as having one deep root, like a carrot, but it's not the case for many," says Sifton. "Roots are very vulnerable within the top six inches of soil."
Try not to cut into tree roots, particularly large ones close to a trunk. "Think of the roots as if they were a fiber optic cable; you don't want to cut one of those," she says.
Above: Avoid compacting the soil above roots. Don't put heavy equipment or machinery on soil that covers a tree's root zone. "Soil compaction is a silent killer," says Sifton. "Compaction presses all the pore space out of the soil, which reduces the ability of water and air to enter the root zone." Photograph by Uli Lorimer.
Above: The Brooklyn Botanic Garden lost a row of 80-year-old Tilia cordatas, linden trees near the western edge of the property. "The trees were lost were mostly due to location," says Sifton. "We took a hit on higher ground, which was predictable. Winds on higher elevations are stronger. If you've got an open area, it will most likely be the first line of trees, the windbreak, that takes the brunt of a really bad storm."
In a home garden, try to site young or fragile trees in a sheltered spot so they don't have to withstand the full strength of winds. Photograph by Elizabeth Peters.
Above: Have a trained arborist evaluate your trees every year or so. Some trees may never need pruning, says Sifton, but others require upkeep. Get an expert's advice and, for safety's sake, don't take it upon yourself to climb up in a tree with a chain saw. "When pruning, a rule of thumb: don’t take off very much living material. Avoid taking off more than 15 percent of portions of a tree living above the ground," says Sifton. Photograph by Elizabeth Peters.
Above: The Tree Care Primer, edited by the Brooklyn Botanic Garden's arborists, covers such topics as how to choose a healthy tree at a nursery; how to care for an elderly or dying tree; and how to pick an appropriate tree for your site. The book is $8.95 from the garden's online gift shop.