Feminized cannabis seeds
Cannabis plants are able to reproduce and grow both male and female plants, as a way of natural survival. Since it's only the female plants that a grower is after in order to harvest trichomes, male plants are not needed. With regular cannabis seeds, it's recommended to germinate and grow a larger amount of seeds in order to be able to remove any resulting male plants and thus preventing them from fertilising the female ones and greatly deminishing the trichome crop yield.
To make life easier for growers, cannabis plants can be modified and selected to just produce the female plants. Feminised seeds are created by forcing a female to produce her own pollen and fertilise other female plants that will contain all female growth characteristics as needed. Feminised seeds will create plants with the same resin production, THC and CBD levels and flavour as comparable regular seeds.
Feminized seed strains make it very easy to just grow and harvest the amount of plants you actually need, without bothering about having to manually check and remove any male species.