With the emergence of the Brood X 17-year cicadas in Spring of 2021, you may notice the tips of branches having died. Trees most susceptible to this type of damage include oaks, maples, cherries and other fruit trees, and redbuds, among others. The University of Maryland Extension reports that cicadas can lay eggs on over 200 types of trees. The damage occurs when cicadas lay eggs on these types of trees.


Life History of Cicadas

The life cycle of a cicada requires them to begin laying eggs a week after they emerge. Cicadas mate and then the females deposit eggs in groups on twigs near the end of branches. Females use their ovipositor to gouge long slits in the twigs into which the eggs are laid. Those twigs with a lot of slits in them are significantly weakened and will often break and bend down, creating what arborists call “flagging”.

For mature healthy trees, this damage is sustainable, and the tree will close up these tips and regrow the branches. For young and newly planted trees, extensive damage could kill them.

Roughly six weeks later, the eggs hatch and the nymphs drop to the ground and proceed to burrow back into the ground at the base of the tree. They sustain themselves from the sap of the tree roots, which typically does not kill a mature tree but may reduce productivity.


Tree Damage from Cicadas

Prior to the emergence of cicadas, it is a good idea to wrap the canopy of any young or newly planted trees with netting. This can also apply to fruit trees that need additional protection to ensure continued productivity. Netting or pesticides are available to help ward off cicadas ready to lay eggs.

If you have a young tree that has sustained a lot of cicada damage, prune tips of the branches within 6 weeks to remove the eggs. This will prevent the nymphs from feeding on the roots of these more susceptible young trees.

If your trees have sustained light cicada damage to the branches that does not exceed roughly 18’’ in length, do not worry. These trees can heal themselves and will recover.


When to take Action on Cicada Damage

For moderate to severe damage, you should monitor these trees and consider having these trees pruned by an arborist. Pruning the tree quickly will help heal these damaged branches and reduce the number of cicadas that borrow and feed on the roots of these trees.

If you notice any other signs that the tree could be dying as a result of cicadas or other pests, let us know, and we’d be happy to take a look and it and any other trees on your property.


Manor Tree Service has been serving Maryland in eastern Baltimore County and western Harford County with unparalleled, expert care for over 4 decades. We stand by our work and are confident you will enjoy a wonderful experience with our team.