Norwegian forest bilberries called the Arctic Blueberry or European blueberry are prized for anti-inflammatory properties and have been used in medicine for over a millenium. Bilberries work well against the flu, angina, and blood disorders. They also are heralded for improinge eyesight, preventing aging, and boosting the immune system. Blue in color while growing on the bush, bilberries change their color into black when picked, and their purple juice is an excellent natural dye. They come in season in late August.