What is on my crape myrtle and how do I get rid of it?

kimjomcsoto · 06-25-2010, 08:05 PM

I was watering my plants today and noticed this white stuff on the branches of my crape myrtle. I'm not sure what it is, but I want it off. I also noticed a lot of little black bugs down at the bottom of the trunk. I will post pictures of what I am seeing. Please help me!!!

chrisn · 06-26-2010, 05:40 AM

I took this off another site but it is the info you need. You can also apply a horticultural oil when the plant is dormant.

What you are referring to is most likely a scale insect. There are many types of scale insects with some of them being as large as a ladybug. They are round on the top and flat on the bottom. They don't move once they have inserted their mouth part into the plant. The feeding releases sugars that black sooty mold grows on. The mold is not harmful to the plant but can cut back on the amount of light the leaves receive. Control is easy--- purchase some Bayer Advanced Tree and Shrub Insecticide at one of the big box stores. It has the active ingredient "imidacloprid". The insecticide is mixed up in a bucket and poured around the base of the plant. Is systemic, so the plant will take it up and kill the scale feeding on the plant. The product will have directions as to how much to use based on the size of the plant. Do this if the plant has leaves and is actively growing. If the plant is dormant, wait until it begins to leaf out and then apply the product. Good Luck.

kimjomcsoto · 06-26-2010, 08:52 AM

Thank you! I'll be going today to get some!!!

downunder · 06-26-2010, 04:06 PM

It's either waxy scale or mealybugs. The mealybugs are actually related to the scale but not quite the same. Treatment for both is the same as already mentioned. However, make sure that you get a "summer" oil and not a dormant oil which is for use in the winter. The heavier oils can burn the foliage during the hotter months.

One way to identify for sure is to squeeze one in you fingers. If it's waxy scale, you will find a small pin-head sized bug that is bright pink/reddish colored inside of the white wax. Your finger will feel like you sqeezed a candle, hence the name "waxy" scale. Mealybugs are little guys that are whitish colored and have 8-10 legs (Can't remember off-hand). Just in case you were wondering.