Chestnut, Walnuts and Almond trees are very large and can serve a dual purpose as a shade tree and food producer. Nuts do best with long hot summers. Many of these nut trees are self-fruitful. Almonds are native to central and southwest Asia, may have been cultivated in the ancient world as early as 4000 B.C. Chestnuts have scattered native species in Europe, Asia, and North America. Chestnuts first recorded in China around 900 A.D. Walnuts and its close relatives are broadly distributed across North and South America, Europe, and Asia. Spanish missionaries first introduced English walnut (Juglans regia) to California in the 1700s and commercial walnut production began in the mid to late 1800s.