Cherries are a nutritious fruit, containing minerals like iron, potassium and other vitamins. American cherries have firm flesh and strong sweetness, while Japanese cherries have smaller pits and a greater amount of soft edible flesh, thus are juicier with an excellent balance of sweet and sour. Edible fruit-bearing cherry seedlings were first introduced to Japan from Europe and the US in the late nineteenth century. Today, various kinds of cherries are grown from central to northern Japan, with Yamagata Prefecture the largest cherry-producer, boasting over 70 percent of total yield. In the early twentieth century, Yamagata farmer Eisuke Sato selectively cultivated the sweet Kidama and the slightly tart Napoleon varieties; after nearly fifteen years, he succeeded in producing the Sato Nishiki cherry, which today is the most commonly cultivated variety. Often sent as a gift, it is expensive: each cherry is handled individually, one by one, and arranged in neat rows in boxes. New high-end varieties are also currently being developed.