Leaf Morphology Narrow Leaflet

Narrow leaflet morphology refers to cannabis plants that express characteristically thin, elongated leaf blades with reduced width-to-length ratios. This trait is commonly associated with sativa-dominant and equatorial landrace genetics, where narrow leaves may offer adaptive advantages in high-light or humid environments. Breeders working in sativa and hybrid programs frequently observe this phenotype clustering with longer internodal spacing and extended flowering windows. Narrow leaflets differ structurally from broad-leafed (indica-type) phenotypes, which display wider, shorter blade geometry. Documentation of this trait remains useful for phenotype classification and parentage verification in breeding records.

Breeders select for or against narrow leaflet expression when targeting sativa-type plant architecture or when breeding for environmental adaptation. This morphological marker often appears linked to flowering time and growth pattern genes, making it a useful visual indicator for early generation selection.