Once crape myrtles lose their leaves in Baltimore, homeowners may assume pest problems have disappeared for the season, too. But bare branches can actually make November an excellent time to take a closer look at your tree.
Small white or gray felt-like bumps along the trunk and branches, blackened bark, or evidence of sticky honeydew from earlier in the season can point to crape myrtle bark scale, an invasive scale insect that feeds on crape myrtles and can remain on the tree through winter.
The good news is that seeing these symptoms doesn’t automatically mean your crape myrtle is dying. But identifying an infestation before winter gives you time to understand its severity and develop an appropriate management plan before pest activity increases again.
What Does Crape Myrtle Bark Scale Look Like?
Crape myrtle bark scale is relatively distinctive once homeowners know what to look for. Here are some tips for crape myrtle bark scale identification:
Start with the Trunk and Branches – After leaves drop, inspect the main trunk, branch crotches, undersides of branches, smaller twigs, and areas around pruning cuts and bark crevices for crape myrtle scale damage.
Look for White or Gray Felt-Like Bumps – Adult female insects produce coverings that may appear as gray or white bumps on crape myrtles. If squished, these coverings will turn bright raspberry red. When populations are high, these bumps can appear in clusters along branches and trunks. Keep in mind that other scale insects and bark features can look similar, making proper identification important for treatment.
Look for Black Bark or Sooty Mold – As scale insects feed, they produce a sugary waste called honeydew. Sooty mold fungi grow on this material, covering trunks, branches, leaves, and other plants and surfaces beneath an infested tree. While sooty mold on crape myrtles isn’t feeding on the tree, it indicates scale insects.
Look Back at Summer Symptoms – Were there sticky crape myrtle leaves or branches, black foliage, ant activity, reduced flowering, or clusters of white material on bark during the summer? Those could have been signs of a crape myrtle scale infestation earlier in the growing season.
What Happens to Crape Myrtle Bark Scale During a Baltimore Winter?
Many homeowners assume freezing weather kills insects living outside, but crape myrtle bark scale can survive winter on infested plants as long as temperatures don’t dip below freezing for an extended period. The pest can overwinter as nymphs on trunks and branches, especially in local warm spots near homes and in sheltered areas where temperatures are warmer.
This lifecycle makes late-fall identification useful even though homeowners may not see obvious active feeding.
Baltimore sits in a transition zone where crape myrtles can thrive, but winters still include periods of freezing weather. Rather than assuming winter will solve an infestation, homeowners should consider the entire pest life cycle:
Late Fall – Leaves drop and infestations become easier to identify on exposed branches
Winter – Crape myrtle bark scale nymphs can overwinter on the bark and beneath bark scales as long as temperatures stay above freezing
Spring – Development continues as temperatures warm
Summer – The mobile, immature stage of crape myrtle bark scale, known as crawlers, emerge and spread to new feeding locations
Scale insects are protected beneath waxy coverings during parts of their life cycle, so treatment depends heavily on which stage the pest is in. Correct identification allows a certified arborist to determine whether crape myrtle bark scale is present, the severity of the infestation, the tree’s health and stress level, and when monitoring and management are appropriate.
Will Crape Myrtle Bark Scale Kill My Tree?
Not every tree infestation is a tree-killing emergency. Established crepe myrtles may tolerate some scale activity, but a certified arborist should treat persistent infestations.
Because crape myrtle bark scale feeds on plant fluids, a persistent infestation can reduce vigor and aesthetic quality, including extensive sooty mold, less attractive bark, reduced flowering, and branch stress when infestations are severe.
A crape myrtle simultaneously dealing with other stressors, including drought, compacted soil, root damage, improper planting, excessive moisture, and other pest or disease problems, may have fewer resources available to tolerate insect feeding.
When Should Crape Myrtle Bark Scale Be Treated?
Treatment depends on identification, infestation severity, the tree’s condition, and the pest's life cycle. Here are some steps to take before determining how to get rid of crape myrtle bark scale:
Step 1: Confirm What You’re Seeing – Avoid treating based solely on a photo or assumption. Scale species differ in biology, life cycle, host plants, and treatment timing. Correct identification should come first.
Step 2: Check Other Crape Myrtles – If several crape myrtles grow on the property, inspect each one. Pay particular attention to branch crotches, lower trunks, shaded portions of branches, and areas with old sooty mold
Step 3: Don’t Assume More Pruning Will Solve It – Removing heavily damaged or dead branches may eventually be appropriate, but aggressive pruning isn’t a substitute for managing the pest because it’s invasive and will keep returning.
Step 4: Develop a Management Plan Before Spring – A professional management plan by a Baltimore certified arborist may include monitoring crawler emergence, cultural practices that support plant health, targeted treatments based on pest life stage, and follow-up inspections. Crape myrtle bark scale treatment recommendations should reflect the individual plant, infestation severity, site conditions, and local pest timing. These treatments may range from systemic insecticides, applications of oil and insect growth regulators, and possibly even manual scrubbing.
Step 5: Monitor Again as Temperatures Warm – Checking the plant again before and during spring development can help determine whether populations are increasing and when susceptible pest stages become active.
Late fall is a useful time to inspect crape myrtles because bare branches can make signs of bark scale easier to see. But successful management starts with identifying the pest and understanding its life cycle, not simply applying a treatment as soon as scale appears.
If you notice white or gray bumps, persistent black sooty mold, declining vigor, or a widespread infestation, a certified arborist can confirm the cause, evaluate your crape myrtle’s overall health, and determine the appropriate timing for management.
Schedule a tree and shrub health inspection with your local Baltimore-area Davey arborist to identify crape myrtle bark scale and develop a management plan for the coming growing season
Crape Myrtle Bark Scale: What Baltimore Homeowners Are Asking
White or gray felt-like bumps attached to the trunk and branches can be a sign of crape myrtle bark scale. Adult females develop distinctive coverings that can become especially noticeable on bare branches. Other scale insects can look similar, including predators that may be trying to help, so proper identification is important before deciding how to manage the pest.
Yes. Crape myrtle bark scale can overwinter on infested crape myrtles. Development resumes as temperatures warm, so identifying an infestation in late fall can help homeowners prepare for monitoring and management during the next growing season.
Scales and aphids are seeking nitrogen in the infected plant and have to shed sugar and water, creating a waste material called honeydew. Sooty mold fungi grow on the honeydew and can make trunks, branches, and leaves appear black. The black coating itself is therefore an important clue that a honeydew-producing insect may be present. Avoid fertilizers with quick-release nitrogen, as this can make the scale problem worse. Slow-release fertilizers and other products without nitrogen can help deter scale insect populations.
Treatment timing depends on the pest’s life stage, local temperatures, infestation severity, and management method. Because scale insects are better protected during certain stages, homeowners should identify the pest and develop a management plan based on local crawler activity rather than treating solely by calendar. Growing Degree Days on the University of Maryland’s Extension website can provide ballpark figures used to predict pest activity.
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Crape Myrtle Bark Scale in Baltimore: What to Look for Before Winter
