FILBERT, the name generally given to the oblong nuts of certain Old World species of hazel (q.v.) chiefly Corylus Avellana and C. maxima. The round nuts of these species are often called cob-nuts. Numerous varieties are extensively cultivated in the Old World, the large nuts of the better kinds forming an important article of commerce, the imports of which into the United States in 1926 amounted to $2,954,000. Excellent varieties are now grown successfully in the States of Oregon and Washington. The plants are trained in tree form, with a single trunk, and become as large as medium-sized apple trees. In the Pacific North-west the trees should be planted about 25 ft. apart each way. In the Eastern States these varieties and seedlings of them are grown in bush form. The Constantinople hazel (C. Colurna) is a large forest tree producing small nuts which are used for seedlings for stocks on which to bud or graft the choice European varieties. The filbert is also propagated by layering the branches to form roots and by digging the suckers or sprouts from the roots. Seedlings are easily grown from nuts stratified over winter, an inch or two deep in soil and planted in the spring. (C. P. C.)