Perennial Garden in Fall.

Mature Tree Care

Nearly 30,000 trees, including thousands that are a century old or older, provide something to celebrate in every season at NYBG. Clouds of magnolia, flowering cherry, crabapple, and dogwood flowers float above the spring landscape, drawing visitors from the Garden’s gates deep into its interior. Ancient oaks cast dense shade in July and August, providing welcome respite from increasingly hot and humid New York summers. The electric oranges, reds, and yellows of sugar maples, tulip trees, and sweetgums in the Thain Family Forest rival those of northern New England forests in fall. The venerable pines, spruces, and firs in the Arthur and Janet Ross Conifer Arboretum remind us that the Garden is very much alive even in the dead of winter.

While their beauty alone would be enough reason to take special care of the Garden’s trees, the additional benefits they provide make their long-term survival all the more important. Collectively, the Garden’s trees remove hundreds of metric tons of carbon dioxide from the atmosphere each year and store tens of thousands of metric tons of carbon within their trunks, branches, and twigs. Our trees and Forest provide habitat for an astonishing array of wildlife ranging from Great-horned owls to mourning cloak butterflies, and even beavers.

Climate change, stresses inherent in the Garden’s urban environment, and a seemingly never-ending parade of new pests and diseases threaten the health of the Garden’s oldest and most majestic trees. To counteract these threats, NYBG arborists employ a range of techniques to keep the Garden’s mature trees healthy. Using compressed air and a tool called a “tree spade,” they alleviate soil compaction caused by decades of trampling feet and turf equipment. They incorporate compost into the soil to feed the fungi and micro-organisms that help tree roots absorb nutrients. They climb our trees, some of which are more than 125 feet tall, to prune out dead or damaged branches, install cables to protect against the loss of major limbs, and adjust lightning protection. An automatic irrigation system allows us to keep our mature trees well-watered during severe droughts.

Together these techniques and others help prolong the lives of the mature trees that are a defining feature of NYBG’s historic landscape. Planting new trees every year ensures that NYBG visitors will have the opportunity to marvel at ancient trees for generations to come.