Narrow Leaflet Morphology

Narrow leaflet morphology refers to cannabis plants displaying characteristically thin, elongated leaf blades—a structural trait distinct from the broader leaflets common in many cultivars. This phenotypic expression is often associated with sativa-type genetics and certain landrace populations, particularly those from equatorial and tropical regions. The trait is controlled by polygenic factors and environmental conditions, making it variable across generations. Narrow leaflets may influence light penetration through the canopy and are frequently noted in breeding records alongside other morphological descriptors. Breeders document this trait for strain characterization and lineage tracking rather than as a primary selection criterion in most modern programs.

Breeders track narrow leaflet morphology as a phenotypic marker for sativa dominance and genetic origin, particularly when working with landrace lines or creating hybrid profiles. The trait can affect canopy architecture and airflow dynamics, making it relevant in cultivation-focused breeding objectives.