Recently I have been consulting on a large tree-planting job. The job is large not only because the trees are large — these evergreens are double the size of many familes’ Christmas trees. The job is also large because at least 20 of these large trees will be planted. Furthermore, the job is large because the 20 large trees will be planted not in a field but in and among the roots of mature trees growing along a woodland border. Because the job is large, I have investigated various ways to make the project easier. Tree-spade planting, the most promising option I found, however, has serious liabilities.
If you need instant impact with a minimum of labor and site disturbance, tree-spade planting is your easiest option. Tree spades come in various sizes, and can move trees as large as 25 feet tall. Imagine a hydraulic machine mounted at the back of a truck that can slice ice-cream-cone-shaped chunks of soil from the ground, with or without a tree in the center. The spade goes to the planting location, and removes an ice cream cone of dirt. Then it goes to the tree and removes an identically sized ice cream cone of dirt with the tree in the center. Finally, it takes the tree and dirt back to the planting hole and sets the tree and soil into the empty hole. It’s like a preschool shapes game. And you have a large tree where you want it in as little as a half-day.
But the story of tree-planting success is not told in a single day.
Best management practices (BMP) for planting trees are oriented to the long-term success of the planting project. The goal of planting (transplanting) a tree is “establishment.” A tree is established in a new site when it has completely recovered from the transplanting, and is equally settled into its new home as it was in its old home before the transplant. The process of transplanting severs as much as 98% of a tree’s roots. These roots have to grow back before a tree is considered “established” in its new home, and during this time, new shoot growth can be limited.
Tree-spade transplanting runs afoul of BMPs in two ways. First, the new hole should be much wider than the root ball of the transplanted tree. Second, the new hole should not have “glazed” walls. A small hole and glazed sides will make it more difficult for fine feeder roots to penetrate the soil of the new hole, slowing transplant recovery. Additionally, it is possible that the tree will never properly root, and the tree will show problems many years later.
Maybe you plan to plant a tree yourself this spring. Follow BMPs to ensure the young tree has the best chance to thrive and deliver all of its benefits.
Reach me at firstname.lastname@example.org.
Joshua Arp is an ISA-certified municipal specialist, Clarks Summit’s municipal arborist and an operator of an organic lawn and landscape maintenance business.