Corylus avellana, or European filbert, is a non-native species from Europe and Asia that produces edible hazelnuts that ripen in late August and September. It prefers moist, well-drained soils, but is fairly tolerant to different conditions. To maintain its appearance and prevent thicket formation, prompt removal of root suckers is necessary. While it's susceptible to eastern filbert blight and occasional issues like black knot, crown gall, and leaf spot, it remains a productive plant when properly cared for. The tree can be moderately messy with fallen nuts, catkins, and leaves, requiring occasional clean-up. Japanese beetles may also target its foliage, and its pollen and nuts could cause allergic reactions in some individuals.