How to Prune Hazelnut Trees. The delicious, sweet nuts and small size of the hazelnut, or filbert tree, make it a welcome addition to a backyard orchard. The native hazelnut (Corylus americana) thrives in U.S. Department of Agriculture plant hardiness zones 4 through 9, while its close relative, the European filbert (Corylus avellana) prefers USDA... Table of contents How to Prune Hazelnut Trees Safety First 00:47 Tree, Shrub or Hedge 01:16 Ornamental Hazelnut Trees 01:55 A Dangerous Infection 02:47 -----------------