Extra select black sunflower seed is sourced generally from europe and the uk this is high oil black sunflower which has also been selected and correctly harvested to produce the maximum oil content black oil sunflower must not be harvested late as this produces a high acid content and must be fully matured or you just get empty husksblack oil sunflower seeds are screened graded and then a little vegetable oil is added to give them extra shine so the birds can spot them more easily its tr