It has consisted in always cultivating the best known variety, sowing its seeds, and, when a slightly better variety chanced to appear, selecting it, and so onwards.
Osperik handieneko aldakia beti haztean egon da gakoa, beti harexen hazia ereinez, eta aldaki hoberik agertzea gertatuz gero, huraxe hautestean, eta hurrengoetan ere horixe egitean.