Sometimes called the Lilac of the South, you can usually find a Crepe Myrtle on every street in town. If you look closely, you might find black soot on the stems and a white cottony substance on top of the soot. This white substance is an insect called Crepe Myrtle Bark Scale.
What we can see with the naked eye are harmless adults, but their younger form is a tiny crawler, and these are a bigger problem. These young crawlers feed on the plant and secrete a sugary, honey dew, which then begins to mold and turn black.
If you see this Crepe Myrtle Bark Scale on your Crepe Myrtle plants, there are a few things you can do.
First, if the plant is small enough, spray the whole plant with a dormant oil. This mineral oil will smother any insects and eggs.
Next, apply a systemic drench around the plant. This insecticide will travel through the roots, up the stem, and out to the leaves.
Crepe Myrtle Bark Scale is a problem that all Crepe Myrtle are likely to get, and although the insect may not kill the plant, the sticky bug and the black mold are an ugly nuisance. So treating your plant now may keep your plant healthy and pretty for the summer to come.
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