The crape myrtle (Lagerstroemia sp.) is native to Asia, and as such, is not really in our area of expertise. Due to the large volume of questions we receive we generally limit our answers to questions dealing with North American native species. However, I can steer you to sources that can answer your question. There are several toxic plant databases listed below. You can check for crape myrtle on these lists. Please note that the absence of Lagerstroemia sp. from these lists does not guarantee that it is non-toxic to horses, but not finding it on the lists makes it less likely to be toxic. To search the lists, I recommend using the scientific name since those names are generally standard, whereas the common names often vary in spelling and usage.
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