The harvest

Still today, cotton is harvested exclusively by hand in September in five consecutive stages, so that at each step only the bolls with the right level of maturity are harvested.
Care taken in the cultivation and the manual harvest prevents the use of pesticides and other chemicals, commonly used in mechanical harvesting.
The bolls are removed from the stem from the ground upwards, so that residues from the leaves and branches which may become detached when gathering the bolls don't get mixed in with the other flocks.

After harvesting the fiber is manipulated many times with the "coltsfoot" method, to manually remove leaves, twigs and any large extraneous particles.
The raw freshly harvested flocks risk being contaminated by plant particles and other foreign matter.

It is therefore the skill of the harvester, and then the spinner in removing residual contaminants, that makes a qualitative difference to the yarn right from the very beginning of the process.