A homeowner’s guide to box tree moths, boxwood leafminer, blight, and smart shrub care in Frederick, Carroll, Howard, and Montgomery Counties
What is Eating Your Boxwoods in Maryland?
If you have boxwoods around your home, you may have noticed something strange happening: leaves that look chewed, brown patches that seem to spread quickly, thin spots inside the shrub, or webbing tucked deep within the branches. And you may have seen a few caterpillars or moths. For many Maryland homeowners, boxwoods are the foundation of their landscaping. The evergreen shrubs frame the front walkway, soften the edges of a patio, or give the landscape a finished look. When they suddenly begin to look ragged, it is easy to wonder whether the plant is dying, diseased, or being eaten by insects.
The short answer is that several problems can affect boxwoods in Maryland, including insects, diseases, weather stress, poor airflow, heavy shearing, and drainage issues. But one pest has received extra attention recently: the box tree moth, an invasive insect that feeds on boxwoods and can cause severe defoliation when infestations are heavy.
For homeowners in central Maryland, this is not just a distant issue. The Maryland Department of Agriculture issued a box tree moth quarantine in March 2026 for Allegany, Frederick, Garrett, and Washington Counties. Because Frederick County is part of that quarantine, homeowners in and around Mount Airy, New Market, Urbana, Frederick, Damascus, Sykesville, Eldersburg, Woodbine, and nearby communities should know what to look for.
The Box Tree Moth: A New Concern for Maryland Boxwoods
Box tree moths are invasive pests that feed on plants in the Buxus family – in other words, boxwoods. The damaging stage is the caterpillar, not the adult moth. These caterpillars hide inside the shrub, feed on leaves, and can be difficult to notice until the plant already looks thin or damaged.
According to the University of Maryland Extension, the box tree moth was first detected in Maryland in July 2025 and is now a pest that homeowners should actively watch for. The U.S. Department of Agriculture warns that heavy infestations can completely defoliate boxwoods. After the leaves are gone, larvae may feed on bark, which can weaken or even kill the plant.
That is why early detection matters. A few chewed leaves may not seem urgent, but a box tree moth infestation can move quickly once caterpillars become established. Homeowners should look beyond the outside surface of the plant and inspect the interior branches, where the caterpillars and webbing may be easier to find.
Signs of box tree moth damage
Possible box tree moth symptoms include chewed or missing leaves, leaves that look skeletonized or papery, green-black insect droppings called frass, loose webbing or silk threads inside the shrub, and green caterpillars with black heads and dark stripes running along the body. The damage can begin in isolated sections of the shrub and then spread, making the plant look patchy, thin, or stripped.
Adult box tree moths are usually white with brown borders on the wings, although darker forms can occur. However, homeowners are more likely to notice the damage or caterpillars than the adult moths. If you suspect box tree moths, take clear photos of the damage, caterpillars, webbing, and the full plant.
Not Every Boxwood Problem Is Box Tree Moths
While box tree moths deserves attention, it is important not to assume every struggling boxwood has this pest. Maryland boxwoods commonly experience several other issues that can produce browning, thinning, or decline. Correct identification matters because the right response depends on the actual cause. Read on for other symptoms of why your boxwoods are not looking great.
Boxwood leafminer
Boxwood leafminer is one of the most common insect problems on boxwoods in Maryland. Instead of chewing the outside of leaves, the larvae feed between the leaf surfaces. This can cause blistered, puffy, yellow, orange, or brownish leaves. A plant with leafminer damage may look off-color or bronzed, especially when infestations are heavy.
Unlike box tree moths, leafminer damage is usually more about distorted or discolored leaves than obvious chunks missing from the foliage. If the leaves look blistered rather than chewed, leafminer may be the more likely culprit.
Boxwood blight
Boxwood blight is a fungal disease that can cause serious damage. Symptoms often include leaf spots, rapid browning, leaf drop, and black streaks or cankers on green stems. The black streaking on stems is one of the clues that helps separate boxwood blight from some other boxwood problems.
Because boxwood blight can spread, homeowners should avoid working with wet plants and should be careful about moving infected clippings or debris. If blight is suspected, it is wise to get an accurate diagnosis before pruning heavily or moving plant material around the property.
Volutella blight and winter injury
Volutella blight often shows up as branch tips turning yellow, tan, or straw-brown. It may affect plants already stressed by winter injury, poor pruning, dense growth, drought, or other environmental pressures. Winter injury can also cause bronzing or browning, especially after harsh temperature swings, drying winds, or sun exposure during cold weather.
These issues can make a boxwood look diseased or insect-damaged even when chewing insects are not the main problem. In many cases, improving plant health, removing dead material, thinning for airflow, and correcting site stress can help the shrub recover or at least slow further decline.
What Homeowners Should Do First If You Suspect It’s A Boxwood Moth Problem
If your boxwoods look damaged, start with an inspection rather than jumping to conclusions. Gently separate the branches and look inside the plant. Check the undersides of leaves, interior stems, and the lower branches. Look for caterpillars, webbing, frass, leaf spots, black stem streaks, blistered leaves, dead branch tips, and excessive leaf drop. Boxwood moths, leafminer, and blight solutions aren’t the same, so you want to be sure.
Take photos before cutting anything. Clear photos are helpful if you need to contact a professional service like A Clean Creation, submit a report, or ask for diagnostic guidance. Photograph the whole shrub, a close-up of the damaged area, any insects you find, and any webbing or unusual stem symptoms.
If you suspect box tree moths, Maryland homeowners should report sightings to the Maryland Department of Agriculture. The state asks for photos of suspected box tree moth or damage. Reporting helps agencies monitor the pest and slow its spread.
Be careful with plant debris
Because box tree moths and boxwood blight can both involve movement concerns, homeowners should be careful about transporting boxwood clippings, infested material, or nursery stock. This is especially important in quarantine areas. Do not casually move suspect boxwood material from one property to another, and avoid disposing of questionable debris in ways that could spread pests or disease.
Avoid unnecessary pesticide applications
It is tempting to spray first and ask questions later, but that is rarely the best approach. Different pests and diseases require different responses, and some pesticide applications may be ineffective, unnecessary, or better handled by a properly licensed applicator. In Maryland, certain treatments may require a certified pesticide applicator. A good first step is diagnosis, not over-treatment.
How Good Landscape Practices Help Boxwoods Stay Healthier
Healthy plants are generally better able to tolerate stress. While good maintenance cannot prevent every insect or disease problem, it can reduce the conditions that allow problems to worsen. Boxwoods do best when they have proper spacing, good airflow, appropriate pruning, consistent soil moisture, and drainage that does not leave roots sitting in saturated soil.
One common mistake is over-shearing. Tight, repeated shearing can create a dense outer shell of foliage that blocks light and airflow from the interior. That dense outer layer can also make it harder to spot insects or disease early. Selective pruning and thinning can help light reach the interior of the shrub and can make the plant easier to inspect.
Mulching also matters. A clean mulch bed helps conserve moisture and improve appearance, but mulch should not be piled against the stems. Keep mulch pulled back slightly from the base of the plant. Excessive mulch against stems can trap moisture and contribute to stress.
Water management is another major factor. Boxwoods do not like extremes. Drought stress weakens plants, while poor drainage can damage roots. If a boxwood is located near a downspout, low spot, compacted soil, or poorly drained bed, the plant may already be stressed before insects or disease appear.
When Boxwoods Can Be Saved And When Replacement Makes Sense
A boxwood with minor damage, a few dead branches, or early insect activity may be worth saving. Pruning out dead material, improving airflow, cleaning up fallen leaves, monitoring new growth, and getting a proper diagnosis can make a big difference. Many homeowners are surprised by how much better a stressed boxwood can look after thoughtful pruning and seasonal care.
However, not every boxwood is worth saving. If a plant is severely defoliated, repeatedly diseased, planted in the wrong location, or part of an older hedge with widespread decline, replacement may be the better long-term option. In some landscapes, the best answer is not to replant the same shrub in the same conditions, but to rethink the planting bed with better spacing, improved drainage, or alternative plants.
For homeowners who love the formal evergreen look of boxwoods, replacement doesn’t have to mean giving up the design. There are boxwood varieties and alternative evergreen shrubs that may perform better depending on the location, sun exposure, deer pressure, drainage, and maintenance expectations. The right solution depends on the property.
How A Clean Creation Can Help
A Clean Creation helps homeowners throughout central Maryland evaluate and maintain their landscapes with practical, property-specific guidance. If your boxwoods are thinning, browning, or showing signs of chewing damage, a professional landscape assessment can help determine whether the issue appears to be insect-related, disease-related, pruning-related, or tied to site conditions.
Services that may help include seasonal landscape inspections, careful pruning and thinning, removal of dead or damaged material, cleanup of fallen leaves and debris, mulch bed maintenance, drainage evaluation, replacement planting recommendations, and ongoing landscape care. If a pest or disease requires treatment outside the scope of landscape maintenance, A Clean Creation can help point homeowners to the next appropriate step, including contacting Maryland Extension, the Maryland Department of Agriculture, or a certified pesticide application when appropriate.
The goal is simple: protect curb appeal, preserve healthy plants when possible, and help homeowners make smart decisions before a small landscape issue becomes a larger and more expensive problem.
FAQ: Maryland Boxwood Problems
What is eating my boxwoods in Maryland?
Several insects can affect boxwoods, but chewing damage may point to a box tree moth problem, especially if you see webbing, frass, or green caterpillars inside the shrub. Boxwood leafminer is also common in Maryland, but it usually causes blistered or discolored leaves rather than obvious chewing.
Have box tree moths been found in Maryland?
Yes. University of Maryland Extension reports that box tree moths were first detected in Maryland in July 2025. The Maryland Department of Agriculture issued a quarantine in March 2026 for Allegany, Frederick, Garrett, and Washington Counties.
What does box tree moth damage look like?
Look for chewed leaves, missing foliage, skeletonized leaves, silk-like webbing, green-black frass, and green caterpillars with dark markings. Damage may appear inside the shrub before it is obvious from the outside.
Will box tree moths kill my boxwoods?
Maybe, if the infestation is heavy enough. According to the USDA, larvae may feed on bark after leaves are gone, which can eventually kill the plant. Early detection improves the chances of protecting the shrub.
Should I spray my boxwoods right away?
Not necessarily. Since boxwoods can be subject to several different maladies, identify the problem first. Spraying without knowing whether the issue is box tree moths, leafminer, mites, blight, winter injury, or site stress can waste money and may not solve the problem. Some treatments may also require a certified pesticide applicator in Maryland.
Why are my boxwoods turning brown if I do not see bugs?
Browning can be caused by winter injury, Volutella blight, boxwood blight, drought stress, poor drainage, over-shearing, or root problems. Lack of visible insects does not automatically mean the plant is pest-free.
Can pruning help damaged boxwoods recover?
Yes, in many cases. Removing dead or diseased-looking branches, thinning dense growth, improving airflow, and cleaning up debris can support recovery. Pruning should be done carefully, and suspect diseased or infested material should be handled appropriately.
Can I move boxwood clippings or damaged plants?
Use caution, especially in quarantine areas or when box tree moths or boxwood blight is suspected. Moving infested or diseased material can spread problems to new locations. When in doubt, contact Maryland Department of Agriculture or University of Maryland Extension for current guidance.
Are boxwoods still a good choice for Maryland landscapes?
Boxwoods can still work well in Maryland landscapes, but they require thoughtful placement, proper pruning, airflow, and monitoring. In some locations, alternative evergreens may be a better long-term choice.
When should I call a landscape professional?
The sooner you can address a boxwood problem, the more quickly you can control it before catastrophic damage. Call a professional when damage is spreading quickly, multiple plants are affected, you are unsure whether the issue is insect or disease-related, or you need help deciding whether to prune, monitor, treat, or replace the shrubs.
About the Author
Charles Kline
Charles Kline is the owner of A Clean Creation, a family-owned landscaping and hardscaping company based near Mount Airy, Maryland. A Clean Creation serves homeowners throughout Frederick, Carroll, Howard, and Montgomery Counties and is a Maryland Home Improvement Commission licensed contractor (MHIC #119932).
With decades of hands-on experience in lawn care, landscape maintenance, drainage solutions, hardscaping, and outdoor living projects, Charles focuses on solutions that help Maryland homeowners protect their lawn and landscaping investments for years to come.
