Once upon a time, the only method breeders had to isolate superior cannabis plant traits was to make basic observations regarding size, structure, or internodal distance. Breeders combined these observations with other practices, such as rubbing the stem of a plant with their thumb and forefinger in an attempt to identify desirable aromatic qualities.
Master Pheno-Hunting: 9 Tips
Given that all genotypes are not created equal, searching for subtle desirable traits throughout a plant's lifecycle can help you select a superior copy of a given genotype.