Are your larger leaf trees, such as maple and linden, that were planted within the last couple of years looking a little rough? Leaf damage with the edges browning and eventually tattered edges from the dry leaf area falling off makes a plant look as though it is dying. While a disease or insect is the first culprit to come to mind, many times it is a form of transplant shock called leaf scorch that is the cause behind the leaf damage.
Leaf scorch is simply described as due to high temperatures and breezy days, the leaves are using or losing more moisture than the roots are taking up, causing the edges of the leaves to dry. During our hot summer days, the water that the roots uptake and travel to the leaves are used for photosynthesis and transpiration. Most of the water is used in transpiration which is releasing moisture into the atmosphere. After planting a tree, it takes several years for the root area to be large enough to uptake enough water to account for all life functions of the tree.
What can the homeowner do to help alleviate the symptoms? Water your plants! Trees planted within the last 2-3 years at a minimum should be watered deeply on an infrequent schedule. What does this mean? Slowly allow water to penetrate the soil so the water soaks to the bottom root area. This may mean having a hose slowly trickle on the plant for 20-30 minutes. Allow the first 1-2 inches of soil to dry out in between waterings. For newly planted trees you may be watering every 3-4 days, increasing the time between waterings as the tree has been planted longer.
If watering is done correctly, leaf scorch is not something that will kill your tree, it will just make it look ugly for a while. With proper watering, as the tree further develops leaf scorch will become less of an issue, and the leaves will remain a dark green season after season.
