You have planted a new tree fresh from the nursery in your yard. Then, you notice that it appears to be dying. Did the nursery sell you a sick tree? Did you plant it wrong?
Try to stay calm. Your tree may not be suffering from an insect or disease. It may simply be something experts call transplant shock.
Causes Of Transplant Shock
Transplant shock occurs when a tree, either young from a nursery or a long-standing tree, is moved to a new area and experiences stress. This condition is common in newly transplanted trees as they try to establish a new root system. When young trees are dug from a nursery, they typically retain only 10-20% of their root system. The rest are left where the young tree originally grew. Thus, newly transplanted trees may be operating with a much smaller root system than what they actually need.
A good comparison is trying to breathe with only a small part of your lungs available. There’s plenty of oxygen around you, but you don’t have the tools available to absorb it. It’s the same with trees that operate with a compromised root system: There may be plenty of water and nutrients in the soil, but if there aren’t enough roots, the tree cannot absorb it.
Experts agree that a newly planted tree typically needs one year for each inch in diameter of the trunk to regain a normal root system. For example, a three-inch diameter newly planted tree will need at least three years in the ground to become fully established.
Symptoms Of Transplant Shock
Despite your best efforts, newly planted may still struggle to become established. Look for the following signs to determine if it could be suffering from transplant shock:
- Wilting, scorching, browning leaves, or early onset of fall colors. Trees that grow with a compromised root system will have limited water availability and may send the wrong signals to foliage, creating off-season coloration.
- Leaf rolling. As leaves dry out, they will often cup or curl to reduce the amount of exposed leaf surface that evaporates moisture. It’s a water saving feature that reduces the loss of water as the tree becomes water stressed.
Transplant shock also makes the tree more vulnerable to pests and diseases. A certified arborist can help to diagnose issues and recommend cultural care options or treatments that may help the tree through a stressful time.
Even though the tree may look like it is dying, a quick scratch with your thumbnail to reveal tissue just under the bark of a small twig will provide evidence that the tree is still trying to grow. If the tissue just under the bark is green and the twig is flexible, there’s a good chance the tree is still viable. If the tissue is brown and the twig cracks when bent, survival is less likely. While pruning newly planted trees for shape is not recommended, experts agree that you should prune away dead or dying twigs.
Preventing Transplant Shock
In order to minimize transplant shock and allow the tree to develop new roots quickly, follow these simple steps:
- Select and plant trees that are native to the region. Native trees are better suited to deal with the local climate and soils.
- Plant new trees at the proper depth. Experts agree that the top of the first lateral root should just barely be visible at the ground surface after planting.
- Water is a key ingredient for new trees to thrive! Long and deep soaking is preferable to a small amount applied every day. Lawn irrigation may not provide the right amount of water since it typically only wets an inch or two of soil where turf roots develop. Proper tree watering will soak much deeper, and then allow soil to partially dry before the next deep soak.
- Unless the soil is heavy clay or very poor quality, it is best to plant a tree with the same soil as you remove from the planting hole. If the planting hole and surrounding soils are very different, tree roots may stay “close to home” in the amended soil within the planting hole and not reach outward to create good structural support.
- Handle trees with care during the planting process. Lift by the root ball when possible to avoid damage to the trunk.
- Apply mulch around the tree at 2-3 inches deep and covering the area under the branch spread of the tree. Do not pile up mulch and create a volcano effect. Instead, create a donut shape that creates a hole, with little to no mulch touching the base of the tree.
- Fertilizing and pruning for shape are not recommended at the time of planting. Only prune dead, dying, broken, and poorly formed branches. After a year, or after the tree has become fully established consider fertilization or additional pruning. Some branches may appear to be “out of place” but might benefit growth by providing energy to just the right places. A certified arborist can perform this pruning or provide guidance on proper care of newly planted trees.
Even though it is mostly out of sight, consider the wellbeing of a tree’s root system to improve the success of transplanted trees. To help prevent transplant shock in your transplanted trees, call your local tree service like Hansen’s Tree Service. A certified arborist can consult with you at your home and advise you on the best planting location and methods for your specific tree as well as how to care for it once transplanted.