Anyone who grows trees and shrubs is likely at times to wish to move them. Transplanting involves digging the tree or shrub, moving it to its new location, and then replanting it. The most difficult of these steps, and the one which requires the most know-how, is digging. This article discusses digging up trees and shrubs to about 10cm (4”) in trunk diameter.
For small plants – up to a trunk diameter of 2.5cm (1”) or so – digging can be done with an ordinary garden spade. It is important to do it right, but the work is not difficult and the odds of success are very good. For trees or shrubs with a trunk diameter over 2.5cm (1”) in diameter, and up to as much as about 10cm (4”) in diameter, there are good options available which make it possible for even the home gardener to transplant successfully. Note, however, that size and weight of the required root ball, and the work involved in transplanting, increases rapidly as the trunk diameter increases. Moving trees with trunks over about 10cm (4”) in diameter is likely to require heavy equipment and specialized expertise. The cost of transplanting increases rapidly as the size of the tree increases, although there is almost no limit to the size of trees which can be transplanted successfully if one is willing to pay the price.
Digging a tree or shrub in preparation for transplanting involves several steps. Various digging techniques can be employed, but no matter what approach is used, these steps must be attended to. The information covered here includes just the bare essentials. There are many factors which should be taken into account if one is to realize the best possible results. These considerations include the species of plant being moved and its condition, the soil conditions, climate, season of the year, and accessibility of the site.
Depending on the digging method used, steps 3 and 4 may be reversed.
|up to 1.3cm||20|
|1.3 to 2.5cm||18|
|2.5 to 3.8cm||16|
|3.8 to 6.4cm||14|
|6.4 to 10cm||12|
|root ball diameter||root ball depth|
When transplanting any plant, preserving a significant fraction of the root system is necessary to maximize the chances of successfully re-establishing the plant in its new location. The practice of root pruning in preparation for transplanting can help concentrate the root system into a more confined area, thereby increasing the fraction of the root system that can be preserved.
In the case of trees and shrubs, the weight of a large root ball, and secondarily the weight of the tree itself, contribute significantly to the effort required to dig and move the plant.
Trees and shrubs of all sizes may be dug up using simple shovels.
Some nurseries use tree spades, which are specialized powered equipment dedicated to digging up trees and shrubs.
A specialized tool for cutting roots may also be used, possibly in conjunction with a leverage-based manual system for lifting the root ball.
In the case of extremely large trees, these have at times been moved by equipment designed for moving missiles.