How do I get rid of crepe myrtle bark scale?
How do I treat for crapemyrtle bark scale? Systemic insecticides work very well to control the bark scale, but the timing is most effective when applied in late winter/early spring. If you are just now spotting the problem, you can clean off the trunk with warm, soapy water to remove the black sooty mold.
What is bark scale on crepe myrtles?
Crape myrtle bark scale is relatively easy to iden- tify. It is one of the only scales known to infest crape myrtles. Adult females are felt-like white or gray encrustations that stick to crape myrtle parts ranging from small twigs to large trunks. When crushed, these scales exude pink “blood”-like liquid.
What is the white stuff on the trunk of my crepe myrtle?
The weird, white stuff is a fungus called powdery mildew. Its spores are everywhere, but they don't germinate unless the conditions are right. And that's what crepe murderers have helped to do this year.
What does the bark of a crepe myrtle look like?
0:384:40Is Your Crepe Myrtle Bark Peeling? It's a Feature, Not a Bug! - YouTubeYouTubeStart of suggested clipEnd of suggested clipAnd you can see the exfoliating bark that's coming straight off of those. And it's revealing kind ofMoreAnd you can see the exfoliating bark that's coming straight off of those. And it's revealing kind of this modeled bark that just looks really cool.
What does crepe myrtle scale look like?
Crapemyrtle Bark Scale (let's call it CMBS) is a small insect that appears as a white or gray felt-like encrustation. CMBS might be found anywhere on crapemyrtles, and often appears near pruning sites and branch crotches of more mature wood. Often times, the first sign of CMBS is the black sooty mold on the tree bark.
What insecticide kills scale?
Acephate, imidacloprid and dinotefuran are three commonly used systemic insecticides that are effective against scale.
How do you get rid of white fungus on crepe myrtles?
The best way to manage powdery mildew on crapemyrtles is to plant resistant cultivars. You should plant them in full sun and in open areas with good air circulation. If established crapemyrtles are infected, prune them to increase air circulation. Remove the small, twiggy growth below and within the canopy.
How do you get rid of crape myrtle fungus?
Spray the infected crepe myrtle trees with copper fungicide or lime sulfur fungicide. Start spraying when the leaf tip symptoms first show up, then repeat every ten days during wet weather.
Does neem oil work on bark scale?
Neem oil, while useful in other applications, will not be effective for this scale in winter. Previously, systemic insecticides in the neonicotinoid family were recommended. These chemicals enter the circulation of plants and kill the pest when they feed on the sap.
Should I peel the bark off my crepe myrtle?
So, if you notice peeling bark on crepe myrtle, leave it alone! This is just one more wonderful way for this tree to actually enhance your landscape and yard. These trees are full of surprises every season. The bark coming off a crepe myrtle is just one way it can surprise you.
How often do crape myrtles shed bark?
Once the tree reaches full maturity, about one to two years after being planted, you can expect bark exfoliation every year in some varieties. Depending on rainfall, other types have been known to shed bark every other year.
What time of year do crepe myrtles shed bark?
Because the Crepe Myrtle is a deciduous tree, it sheds all its leaves during the winter, leaving behind the beautiful bark on the tree which makes it a centerpiece in many winter landscapes.
What is the difference between bark scale and Mel scale?
The bark scale is physiological scale in which bandwidth is constant. Therefore, number of filters and critical band selection are primary for Bark scale filter bank. Mel scale is psychological scale in which as increment in the filter number increases the bandwidth thereby increasing the recognition rate.
Why is bark peeling off crepe myrtle?
Crepe Myrtle Bark Shedding – A Perfectly Normal Process It occurs after the tree has reached full maturity, which may be a several years after you plant it. Crepe myrtle bark shedding is a normal process to these trees. They are often prized because of the coloration that shows up on their wood once the bark is shed.
What causes scale on trees?
The scales tend to be more numerous on trees that are already under stress from causes such as drought or construction damage. You will need to consider the number of scale insects on your tree and the tree's overall condition before deciding whether or not to treat it with an insecticide.
Does neem oil work on bark scale?
Neem oil, while useful in other applications, will not be effective for this scale in winter. Previously, systemic insecticides in the neonicotinoid family were recommended. These chemicals enter the circulation of plants and kill the pest when they feed on the sap.
White Scale on Crepe Myrtles
Adult white scale is a tiny grey or whitish pest easily identified by its waxy, crust-like covering. It can appear anywhere, but is often seen on b...
How to Treat Crepe Myrtle Bark Scale
Crepe myrtle bark scale treatment may require several different techniques, and management of the pest requires persistence.Scrub the pests away –...
Crepe Myrtle Bark Diseases from Scale
If your crepe myrtle is affected by white scale, it may develop black sooty mold (In fact, the sooty, black substance may be the first sign of whit...
How to control crapemyrtle bark scale?
Effective management of crapemyrtle bark scale relies on good monitoring practices to ensure that pesticides are targeted towards vulnerable stages. Spraying contact insecticides on egg sacs or pupae may have very little efficacy. Applications should be timed to target crawlers or immature nymphs before coating themselves in the white wax. Crawler activity appears to peak between mid-April to beginning of May for several locations across Texas and Louisiana. To determine crawler activity at your location, consider using double-sided sticky tape traps around the branch of the tree. Remove and replace with a new piece of tape weekly, and check tapes for presence of crawlers (see images below). When numbers of crawlers start to increase, consider control measures below.
How does crapemyrtle bark scale spread?
Short distance spread likely occurs via wind or by hitchhiking on birds, mammals and larger flying insects.
What is the scale on a crapemyrtle tree?
The crapemyrtle bark scale, Acanthococcus (= Eriococcus) lagerstromiae (Kuwana), was first confirmed in the USA in 2004 in the landscape near Dallas (TX), although it was likely introduced earlier. The scale is a sucking insect that feeds on the phloem (sap) of plants. As it feeds, it excretes a sugary solution known as “honeydew” (similar to aphids, whiteflies, and other sucking insects). Heavy infestations of crapemyrtle bark scale produce sufficient honeydew to coat leaves, stems and bark of the tree. This honeydew, in turn, will eventually turn black as it is colonized by a concoction of fungi, called sooty mold. Although crapemyrtles rarely die as a result of crapemyrtle bark scale infestation, the sticky leaves and black trunks greatly reduce the attractive appearance of the tree.
Why is my crapemyrtle bark black?
Heavy infestations of crapemyrtle bark scale produce sufficient honeydew to coat leaves, stems and bark of the tree. This honeydew, in turn, will eventually turn black as it is colonized by a concoction of fungi, called sooty mold. Although crapemyrtles rarely die as a result of crapemyrtle bark scale infestation, ...
What is the stage of a tree that disperses?
Life Cycle. After hatching, the scale emerging from the egg is called a crawler. This first life stage (1st instar) is mobile and is the only stage that can disperse (via wind or animal transport). Once settled on the tree, the crawler remains in the same spot for the remainder of its immature life.
What to do if you live outside of Texas?
If you live outside of Texas, contact your local extension for management options.
Is crapemyrtle bark scale invasive?
Miller et al. (2017). Crapemyrtle bark scale: a pretty plant, an invasive pest, and a plan to protect pollinators. Poster.
What is the bark scale on myrtles?
What is bark scale on crepe myrtles? Crape myrtle bark scale is a relatively recent pest that is affecting crepe myrtle trees in a growing area across the southeastern United States. According to Texas AgriLife Extension, this harmful pest is newly introduced from the Far East.
What is the white scale on my crepe myrtle?
If your crepe myrtle is affected by white scale, it may develop black sooty mold (In fact , the sooty, black substance may be the first sign of white scale on crepe myrtles.). This fungal disease grows on the sweet substance excreted by white scale or other sap-sucking insects such as aphids, whiteflies or mealybugs.
How to treat Japanese beetles on a tree?
A soil drench will also control aphids, Japanese beetles and other pests. Spray the tree with a dormant oil – Apply dormant oil generously, using enough oil to reach cracks and crevices in the bark. You can use dormant oil between the time the tree loses its leaves in fall and before new foliage emerges in spring.
How to get rid of black mold on a tree?
Scrubbing will also improve the appearance of the tree, especially if the scale has attracted black sooty mold. Mix a light solution of liquid dish soap and water, then use a soft brush to scrub the affected areas – as far as you can reach.
What is white scale?
Adult white scale is a tiny grey or whitish pest easily identified by its waxy, crust-like covering. It can appear anywhere, but is often seen on branch crotches or near pruning wounds. If you look closely under the waxy covering, you may notice clusters of pink eggs or tiny nymphs, which are known as “crawlers.”.
Is sooty mold a fungal disease?
This fungal disease grows on the sweet substance excreted by white scale or other sap-sucking insects such as aphids, whiteflies or mealybugs. Although sooty mold is unsightly, it is generally harmless. Once the problem pests are controlled, the sooty mold problem should resolve. Printer Friendly Version.
What is the mold on my crape myrtle?
Even mulch and plants growing beneath crape myrtles heavily infested with crape myrtle bark scale will be covered with sooty mold. Crape myrtles that are heavily infested with CMBS are covered with sooty mold and bloom poorly. Note that the mulch underneath this tree is also black with sooty mold.
Why are crape myrtles used in landscapes?
Plant Selection. Because of their unique beauty and toughness, crape myrtles are widely used in southern landscapes. However, because of CMBS, landscape planners are encouraged to consider including some alternative species in the landscapes to increase planting diversity.
How to identify crape myrtle scale?
Heavy infestations of crape myrtle bark scale are easy to spot and identify: Look for crape myrtles with heavy accumulations of black sooty mold on the leaves, limbs, and trunk. Adult female scales are covered with a soft, off-white felt-like material and are about one-tenth of an inch long.
What causes black mold on myrtles?
The nymphs produce large quantities of honeydew, and this results in heavy accumulations of sooty mold on the leaves, twigs, and trunks of infested plants, as well as on nearby low-growing plants and surrounding grass and mulch. The end result is a crape myrtle that is black and ugly (due to heavy sooty mold accumulation ) and produces fewer and smaller blooms. Unless they are treated, crape myrtles that are heavily infested with CMBS become a landscape eyesore. Effective treatments are available, but they are relatively costly and do not provide 100 percent control, meaning that treatments must be reapplied each year.
Why are myrtle trees black?
Heavy infestations of crape myrtle aphids will also cause trees to be black with heavy accumulations of sooty mold. Although they also occur on the trunk and lower limbs, many CMBS will be on smaller branches and twigs higher in the tree.
How to protect crape myrtle from CMBS?
The simplest and most effective defense against CMBS is to avoid buying and planting infested crape myrtles. Work closely with the nursery where plants are purchased to be sure plants are free of crape myrtle bark scale. Inspect plants carefully before purchase. Although heavy infestations are easy to detect, low-level infestations are not, and even a single live female or a single egg sac filled with eggs is still an infestation. Mississippi nurseries are encouraged to be especially vigilant for CMBS in order to avoid selling infested plants. Builders and landscape contractors should take special care to be sure any crape myrtles being installed around new homes or commercial landscapes are free of CMBS and come from reputable nurseries. New homebuyers should inspect any crape myrtles present on the property they are considering.
What is a Crape Myrtle Bark Scale?
Crape myrtle bark scale (CMBS) is a serious new threat to southern crape myrtles. It threatens to turn what has historically been a beautiful, low-maintenance landscape tree into an unsightly, high-maintenance landscape tree. This nonnative scale was first detected in the United States in Texas in 2004 and was first found in Mississippi in spring ...
How can I identify crapemyrtle bark scale?
Careful examination may reveal dozens of pink eggs or crawlers under some of the larger white scale covers.
Will crapemyrtle bark scale kill my trees?
No need to remove your trees if you suspect infestation. However, treatment is necessary. The scale will NOT kill your trees but they reduce the amount and size of the blooms and the sooty mold makes them less attractive.
How can I keep scale from spreading?
Do not put them in a compost pile, or put them out on the curb for yard-waste pick-up. In a perfect world, burning the debris would be the best way to eradicate the pest, but unfortunately we can’t burn refuse in the city.
What is the invasive pest that can destroy the aesthetic value of crapemyrtle?
Crapemyrtle bark scales are an invasive pest that can destroy the aesthetic value of crapemyrtle.
What is a crapemyrtle scale?
Crapemyrtle bark scales (Figure 1) are an invasive insect that feed primarily on ornamental crapemyrtle. While they rarely kill crapemyrtles outright, crapemyrtle bark scales negatively affect the aesthetic value of infested plants by decreasing the size and abundance and of flowers, causing stunting and branch die back, ...
How many eggs do crapemyrtle nymphs lay?
Female crapemyrtle bark scales construct white, felt-like sacs in which they lay 100–300 pink eggs (Figure 2). Once the eggs hatch, the crawlers move to new areas of the host to feed (Figure 3). They molt into sessile nymphs that lack legs and feed in place without moving. Mature nymphs either molt into females or spin a white sac and molt into “prepupae", then into “pupae", then into adult males (Figure 4). Nymphs and females feed and secrete honeydew. In southern areas, there are 2–4 generations per year and all stages are capable of overwintering. It's unclear how many generations may occur in Pennsylvania.
What zone do crapemyrtles grow in?
Most crapemyrtles can be planted in USDA Hardiness Zones 6-10 and some cold hardy cultivars are marketed as surviving Zone 5. The red isothermal lines indicate the predicted limits of crapemyrtle scale range and were adapted from Wang et al. (2019).
What is the only scale that infests crapemyrtle?
Crapemyrtle bark scales are the only bark scales that infest crapemyrtle in North America, so identification is relatively straightforward. The most obvious life stages are mature females and males, which spin white coverings under which they lay eggs or metamorph into adults, respectively (Figures 2, 3).
How many species of parasitoid wasps are there in the world?
Sixteen species of parasitoid wasp have been reported from crapemyrtle bark scale worldwide. Some of these species occur in the United States but have not apparently been recorded from crapemyrtle bark scale yet. Additionally, two species of green lacewing have been reported to feed on crapemyrtle bark scales in Asia.
Where are crapemyrtle scales found?
Crapemyrtle bark scales were first found in Richardson, Texas in 2004. Since then, they have spread across 14 states and Washington, D.C. (Figure 6). Infestations appear scattered across the southeast rather than moving in a distinct wave across the region, which suggests they are likely being transported primarily through infested nursery stock. Modeling studies suggest that crapemyrtle bark scales will be able to persist throughout the potential range of crapemyrtle in North America, including most or all of Pennsylvania (Figure 7).
Why are my crape myrtles not blooming?
Thanks for your comment. Several factors can cause Crape Myrtles to not bloom, or bloom far less than others around DFW. One cause is underwatering. Notice how beautiful the Crape Myrtles look around town after a nice rain passes through? Another cause is too much shade. As nearby shade trees grow and mature then the crape myrtles are left hidden underneath and struggle to get enough sunlight. Third cause could be tree stress and shock from pests. Scale and aphids are the biggest nuisances that I see on crape myrtles. As far as treatment goes, we do not feel that the oils, soaps, and washes from other sites work. We of course wish that more organic options really worked, but sadly they do not seem to be effective enough. I would say give them a try if you would like and then you can try the Bayer if all else fails. Bayer will have a 100% success rate on wiping out the scale. Good luck to you and we greatly appreciate you reading out blog. <3 - Denise
What does a crape myrtle bark look like?
Bark Scale along the branch of a Crape Myrtle. Many people who call us describe their trees as covered in white dots, or white cotton like bumps. They often think the white dots are a fungus, but it is in fact a bug. If you smash one when it’s alive it will actually ooze a reddish-pink liquid.
Why do I have crape myrtles?
Third cause could be tree stress and shock from pests . Scale and aphids are the biggest nuisances that I see on crape myrtles.
Where does bark scale come from?
Bark scale originates from China and was brought to the U.S. in 2010. A&M has identified this pest as Eriococcus lagerstroemiae, and suspects that it was brought into the U.S. on a crape myrtle plant. Many people who call us describe their trees as covered in white dots, or white cotton like bumps.
What does black sooty mold look like?
Black sooty mold literally looks like black dust on your leaves and bark. The scale sucks the sap from your branches and tree trunks and then the sugars and yeast in the sap attracts the mold. They go hand in hand, but black sooty mold is really just a cosmetic issue.
How to kill scale on a tree?
To kill the scale we recommend Bayer Advanced Tree and Shrub Protect and Feed Concentrate. It comes in granular and liquid form, and provides 12-month long-lasting systemic protection against the scale. The application rate depends on the tree trunk size, so you will just need to measure around the tree trunk and then pour the appropriate portion of granules or liquid around the base of the tree. Please read Bayer’s label for application rates needed for your tree, and for additional information. This product is readily available online and at most local home & garden stores such as Lowes and Home Depot.
Do crape myrtles live in North Texas?
We Texans sure do love our crape myrtles, unfortunately so does this fairly new pest to North Texas called bark scale. Do not fear though, as it’s easy to treat. Crape myrtles are a very hardy trees with lots of reserves, so it would take several seasons of bark scale for the tree to succumb to this pest. Bark scale originates from China and was brought to the U.S. in 2010. A&M has identified this pest as Eriococcus lagerstroemiae, and suspects that it was brought into the U.S. on a crape myrtle plant.
What is a Crapemyrtle Bark Scale?
Crapemyrtle Bark Scale (let’s call it CMBS) is a small insect that appears as a white or gray felt-like encrustation. CMBS might be found anywhere on crapemyrtles, and often appears near pruning sites and branch crotches of more mature wood. Often times, the first sign of CMBS is the black sooty mold on the tree bark.
How to measure crapemyrtle?
To measure the crapemyrtle, add up the circumference of all trunks at chest high (about 4.5 feet off the ground). For example, if you have 5 trunks and the trunk circumference is 4 inches each, then you have a total of 20 inches in circumference. The drench will need to be applied to the drip line of the plant.
When to apply a crapemyrtle drench?
The best window for control is late April or early May as the crapemyrtles begin to really flush, and can be applied through July. Apply a soil drench of an imidacloprid product such as Ferti-Lome Tree & Shrub Systemic Insect Drench during this period. If CMBS are in your area, it would be a good idea to apply this as a preventative measure during this window. This imidacloprid product is a soil drench that is watered into the root zone, specifically in the drip line of the tree (above graphic) where the feeder roots are located.
How to get rid of a tree that is defoliating?
Once the tree defoliates or before it puts on new foliage, spray with a dormant oil. This can be done multiple times. Apply thoroughly, making sure to get the product under crevices in the bark and between branches .
How to treat a bonide plant?
Treat with Bonide Systemic Insect Spray using a hose end sprayer. This should be done after blooming has ended for the season. Be sure to coat the trunk thoroughly. As with all chemicals, use as directed on the label only.
Can a CMBS overwinter?
CMBS might be able to overwinter in the adult female and egg life stages, and crawlers and later stage nymphs have been observed overwintering under the loose bark and in cracks and crevices of crapemyrtles in our area. In one year, there could be at least two generations of CMBS.
How to get rid of scales on a tree?
Mix dishwashing soap with water and scrub the branches with a soft bristle brush. Although this step isn’t completely necessary, it can reduce female scale insects and egg masses and make chemical controls more effective.
Scouting and Identification
Biology
- Crapemyrtles suffer aesthetic damage because of the CMBS infestations. These bark scales may not kill the plants, but there may likely be a reduction in plant vigor, number of flowers, and flower cluster size. Infested plants typically leaf out later than healthy plants. Branches and trunks can be covered in the white scale infestation. Another str...
A Ray of Hope
Control
References
- Crape myrtle bark scale, Eriococcus lagerstroemiae, belongs to a special group of scale insects known as felt scales. Adult females produce a white, felt-like sac around their bodies and lay approximately 100 to 300 pink eggs inside this sac. The female’s body shrinks as eggs are produced. Eggs hatch into tiny pink crawlers, and the older nymphs ar...