Crapemyrtle Spelling: Why One Word Is Correct

I spell it "crapemyrtle" (one word) for consistency, following Dr. Michael Dirr's Manual of Woody Landscape Plants. Dr. Carl Whitcomb, a noted breeder, explains the botanical reasoning:

The plant belongs to genus Lagerstroemia, family Lythraceae—not Myrtus (family Myrtaceae). It only resembles a myrtle. True myrtle (Myrtus communis) is two words. Standardized plant names treat such compound names as single words (e.g., horsechestnut, dogwood, soapberry) to avoid confusion. Splitting "crapemyrtle" into two words is a modern error, often driven by spell-checkers.

While "crape myrtle" and "crepe myrtle" are common, the single-word form is botanically accurate and preferred by experts.