Crepe myrtles are known for their vibrant flowers and attractive, peeling bark. These beautiful trees are a staple in many landscapes. However, an alarming issue of white spots often interrupts the beauty of crepe myrtles, causing concern for many gardeners and homeowners. This article aims to demystify the cause behind these white spots, highlighting the importance of identifying and addressing this issue promptly.
Often mistaken for a fungus, the white spots on crepe myrtles are actually a clear sign of a pest problem. Understanding that they are not a fungal infection helps in adopting the right treatment strategy. This article will also dispel other misconceptions surrounding the appearance of white spots on crepe myrtles, helping you to manage and care for these beautiful trees better.
Protecting our crepe myrtles from white spots is not just about preserving their aesthetics. It is pivotal in maintaining the overall health of the trees, ensuring their ability to continue providing beauty and shade in our gardens. Join us in exploring the cause of white spots on crepe myrtles, their effective treatment, and long-term prevention strategies.
In This Article
Understanding White Spots on Crepe Myrtle
What are the White Spots?
The white spots that dot the otherwise smooth bark of crepe myrtles can indeed be a cause for concern. They are small, round, and cotton-like. Initially, they may appear as isolated specks, but eventually, they can crowd together to cover significant portions of the trunks and branches. Their appearance is often mistaken for a type of fungus due to their white, spotted presence on the plant.
However, contrary to common belief, these white spots aren’t fungal infections. They are, instead, a sign of the presence of a tiny pest known as bark scale. This distinction is crucial as it directly influences how you tackle this issue.
The Pest Behind the Problem: Bark Scale
The culprit behind these white spots is a small bug named Eriococcus lagerstroemiae, more commonly known as bark scale. The bark scale is not native to the United States. It made its way from China and was first identified on crepe myrtles in the Dallas, Texas region around 2010.
Bark scale are tiny insects that produce a cottony-like substance, giving them their characteristic white or greyish appearance. They latch onto the bark of the crepe myrtle tree, sucking the sap and leaving behind these tell-tale, bothersome white spots. Individually, they might look like harmless specks, but collectively, they can cause significant damage to the tree if left unchecked.
Black Sooty Mold: The Uninvited Guest
Where there’s bark scale, a secondary problem often follows—black sooty mold. While this mold is generally harmless to the crepe myrtle, it can be alarming for gardeners to see their trees’ bark turn black.
When the bark scale insects feed on the tree’s sap, they excrete a sugary substance known as honeydew. This sticky substance attracts a type of fungus, known as sooty mold. The mold feeds on the honeydew and takes residence on the tree’s surface, creating a black, soot-like coating. This is where it gets its name: black sooty mold.
Unlike the white spots caused by the bark scale, the black sooty mold doesn’t cause direct harm to crepe myrtles. It’s primarily a cosmetic issue and will typically disappear once you’ve dealt with the underlying bark scale issue. However, in severe cases where extensive coverage of sooty mold inhibits photosynthesis, it might indirectly affect the tree’s health.
Understanding the connection between the white spots and the black sooty mold can facilitate a more effective approach to managing their presence and impact.
Treating Bark Scale Effectively
While bark scale can be a nuisance, it’s a problem that can be effectively managed with the right treatment.
The Recommended Solution: Bayer Advanced Tree and Shrub Protect and Feed Concentrate
If you’re dealing with a bark scale infestation, the recommended solution is the Bayer Advanced Tree and Shrub Protect and Feed Concentrate. This product is a dual-action formula that not only feeds your tree but also provides systemic protection against pests, including bark scale.
The systemic insecticide moves throughout the entire plant, from the roots to the branches, reaching the pests wherever they are hiding. It offers 12-month long-lasting protection, ensuring your crepe myrtles are effectively guarded against future infestations.
The Bayer Advanced Tree and Shrub Protect and Feed Concentrate is available in both granular and liquid forms, providing flexible application options to suit your needs. The application rate will depend on the size of the tree trunk.
For effective treatment, it’s crucial to apply the product at the right time of year. The best time to treat bark scale on your crepe myrtles is between May and July. During these months, the bugs are active and most vulnerable to treatment.
It’s worth noting that applying too early, while the bugs are still dormant, or too late, when they’ve laid their next batch of eggs, might reduce the effectiveness of the treatment. Always follow the manufacturer’s instructions to ensure the most effective treatment.
After Treatment: What to Expect
Following the application of the Bayer Advanced Tree and Shrub Protect and Feed Concentrate, it’s crucial to know what to expect.
Firstly, you’ll notice that the scale insects will die and leave behind a white shell. This is a visible sign that the treatment is working. The white shells are the dead bodies of the bark scale that remain attached to the tree, creating a somewhat ghostly appearance.
These shells can take time to fall off the tree naturally. The timeframe varies depending on the severity of the infestation and the tree’s natural shedding process, but it could take anywhere from a few weeks to several months.
If the presence of these white shells affects the aesthetic appeal of your crepe myrtle, you can gently brush them off with a soft brush. However, be careful not to damage the tree’s bark in the process.
Remember, patience is key during this process. While it might take time for your crepe myrtle to fully recover and return to its healthy, vibrant state, rest assured that the treatment is useful in combating the white spots and preventing future infestations.
Crepe Myrtle: A Resilient Choice for Gardening
Despite the occasional pest problem, crepe myrtles remain a resilient choice for gardening. The beauty they add to the landscape with their colorful blooms and distinct bark is undeniable. But their aesthetic appeal is not the only reason why they continue to be a favorite among gardeners.
Crepe myrtles are known for their hardiness and adaptability. These trees are tough and can thrive under various conditions. They are also resistant to common fungal diseases, including powdery mildew, making them a valuable addition to any garden or landscape.
Although the white spots caused by bark scale may seem daunting, remember that crepe myrtles are resilient and can bounce back from such issues with adequate care and treatment. Indeed, these trees are worth the effort, given the beauty they offer and the shade they provide.
Crepe myrtles are a testament to the fact that with the right care, plants can overcome pest issues and continue to thrive. So, don’t let the white spots deter you. With the right treatment, you can restore your crepe myrtles to their former glory and continue to enjoy their beauty in your landscape.
Prevention and Long-Term Care for Crepe Myrtle Trees
Proactive measures and regular upkeep can go a long way in preventing the appearance of white spots on your crepe myrtle trees.
Here are some methods to help foil a bark scale invasion before it gets a chance to establish:
Regular Pruning: Pruning your crepe myrtles allows better air circulation and sunlight penetration through the branches, creating a less hospitable environment for the bark scale. This process can also help in removing the infested branches, thereby reducing the population of the pest.
Routine Inspection: Checking your crepe myrtles regularly for signs of bark scale can help in early detection and treatment. Pay special attention to the undersides of branches and the trunk, where bark scale is likely to begin their infestation.
Proper Watering and Fertilization: Adequate watering and the right use of fertilizer can strengthen your crepe myrtles and make them less susceptible to pests. Avoid over-fertilization, as excessive nitrogen can spur lush growth, making trees more appealing to pests.
The appearance of white spots caused by bark scale is more than an aesthetic issue. If left unchecked, it can impact the overall health and growth of the crepe myrtle trees. Therefore, it is crucial to adopt a proactive approach towards tree care, ensuring the well-being and longevity of these beautiful trees.
Summary Of Discussion
Crepe myrtles, with their vibrant blooms and unique bark, are a worthwhile addition to any landscape. Despite the occasional issue with white spots caused by bark scale, with proper understanding, proactive care, and effective treatment, these trees can thrive and continue to beautify our gardens.
In this article, we’ve explored the cause of the white spots on crepe myrtles, debunked misconceptions, and presented effective solutions to address the problem. We’ve also highlighted the importance of regular tree care and the role it plays in preventing such issues.
Remember, the resilience of crepe myrtles makes them capable of bouncing back from pest infestations. Early detection, the right treatment, and continuous care can help ensure that these trees remain a vibrant and valuable part of your landscape.
While pest issues like bark scale can be a challenge, they are certainly not a deal-breaker. With the information provided in this article, you’re better equipped to deal with white spots on your crepe myrtles, ensure their health, and enjoy their beauty for many years to come.
Frequently Asked Questions (FAQs)
What are the white spots on my Crepe Myrtle leaves?
White spots on Crepe Myrtle leaves are often a sign of powdery mildew, a fungal disease that forms white, powdery-looking patches on the leaves’ surfaces.
What causes powdery mildew on Crepe Myrtle leaves?
Powdery mildew is typically caused by warm, humid conditions and poor air circulation. It thrives in crowded and damp environments, making it common in late summer and early fall.
How can I effectively treat white spots caused by powdery mildew on my Crepe Myrtle?
To address powdery mildew, use a fungicidal spray specifically formulated for powdery mildew control. Prune affected branches to improve air circulation and reduce humidity around the plant. Avoid overhead watering and water at the base to keep leaves dry.
Are there other potential causes of white spots on Crepe Myrtle leaves?
While powdery mildew is a common cause of white spots, other factors like scale insects or mealybugs can also create white, waxy deposits on leaves. Identifying the underlying issue is crucial for effective treatment.
Can I prevent white spots from appearing on my Crepe Myrtle leaves?
Yes, you can prevent powdery mildew and other issues by planting Crepe Myrtles in well-spaced, sunny locations with good air circulation. Regularly inspect your plants for pests and diseases, and apply preventive fungicides if conditions are favorable for powdery mildew development.