شمعلة

Also known as cresting

thumb|275px|Wyethia helianthoides or mule's ear wildflower (on right) showing fasciation thumb|200px|A "crested" saguaro cactus (Carnegiea gigantea), resulting from fasciation, located at Saguaro National Park (West), Arizona, U.S. Fasciation (pronounced , from the Latin root meaning "band" or "stripe"), also known as cresting, is a relatively rare condition of abnormal growth in vascular plants in which the apical meristem (growing tip), which normally is concentrated around a single point and produces approximately cylindrical tissue, instead becomes elongated perpendicularly to the directio