As July temperatures climb, insect populations explode. Many tree pests are more than just a nuisance—their feeding can weaken trunks and branches, making trees susceptible to breakage. For homeowners in Gaithersburg, Montgomery County and surrounding areas, learning to spot signs of infestation early can save trees and prevent costly damage. Healthy trees are less likely to host pests and are better able to recover from minor feeding.
Emerald Ash Borer: The Ash Tree Killer
The emerald ash borer (EAB) is perhaps the most notorious pest in Maryland. This invasive beetle has killed millions of ash trees across the eastern United States and is well‑established in Maryland. EAB larvae burrow under the bark and carve serpentine tunnels through the tree’s cambium—the layer that moves water and nutrients—eventually starving even a large, healthy ash within three years.
How to Spot an EAB Infestation
Early detection of EAB is difficult because symptoms appear gradually. Signs to watch for include:
- Thinning canopy: The top third of the tree starts to thin out and die back.
- Sprouting below the canopy: In response to crown dieback, the tree may push out new shoots and branches lower on the trunk or main branches.
- D‑shaped exit holes: Adult beetles chew their way out of the tree, leaving small holes shaped like the letter “D.”
- Woodpecker damage: Woodpeckers feed on EAB larvae; bark that has been stripped away in patches (sometimes called “blonding”) is a red flag.
- Serpentine galleries under the bark: If you peel back loose bark, you may see S‑shaped tunnels carved by the larvae.
- Vertical bark splits: As the tree weakens, the bark may begin to split vertically.
If you suspect EAB, consult a certified arborist right away. Treatment is possible for high‑value trees if the infestation is caught early, but injections must be done by a professional and repeated regularly. Once more than 50 % of the canopy is gone, removal and replacement with a different species is usually more practical.
Other Summer Pests to Watch For
In addition to EAB, several other insects can damage Maryland trees in summer. Bagworms and Japanese beetles defoliate pines, spruces and ornamental trees, leaving them ragged. Spider mites suck sap from leaves during dry spells, causing stippling and leaf drop. While these pests rarely kill a tree outright, heavy infestations can stress trees and predispose them to disease. Maintaining tree vigor with proper watering, mulching and soil care is the best defense. Monitor your trees regularly for chewed leaves, silken bags or webbing, and sticky residue on leaves (a sign of sap-sucking insects). Remove infested branches if possible and contact a tree care professional to discuss treatment options.
Prevention and Management
An integrated approach can help keep summer pests under control:
- Maintain tree health: Water deeply during dry periods and mulch around the drip line to conserve moisture and regulate soil temperature. Healthy trees can better resist pests and recover from minor damage.
- Monitor regularly: Inspect your trees every few weeks for signs of pests or disease. Catching problems early makes treatment more effective.
- Avoid heavy pruning in summer: Heavy pruning can stress trees and invite insect infestations. Remove only dead or hazardous limbs until the dormant season.
- Call a professional: If you notice thinning canopies, exit holes or large-scale defoliation, contact J & B Tree Services. Certified arborists can diagnose the problem and recommend safe, effective treatments. They can also advise whether treatment, monitoring or removal is the best option.
Protect Your Trees with Expert Care
Preventing pest damage is easier than dealing with it after the fact. Routine inspections, good watering practices and timely professional intervention reduce the risk of serious infestations.
J & B Tree Services, LLC provides insect and disease diagnosis, pruning, and tree removal throughout Gaithersburg and Montgomery County. Call
240‑361‑7705 to schedule an inspection and keep your trees healthy all summer long.
