Carya ovata – Shagbark Hickory Tree
Shagbark hickory is probably the most distinctive of all the hickories because of its loose-plated bark. Common names include shellbark hickory, scalybark hickory, shagbark, and upland hickory. Shagbark is evenly distributed throughout the Eastern States and, together with pignut hickory, furnishes the bulk of the commercial hickory. The tough resilient properties of the wood make it suitable for products subject to impact and stress. The sweet nuts, once a staple food for American Indians, provide food for wildlife.
This shagbark at the Morton Arboretum was planted as an acorn 25 years ago. I’d say this demonstrates a fairly slow-growing tree. I’ve planted sugar maple that reached this size in 10 years. Shagbark wood is hard, strong, tough and elastic, and is used in handles for tools and in athletic equipment. The wood also makes excellent firewood, and often is used in smoking meat. Squirrels are extremely fond of the fruit of the hickory, and some humans also use the nuts in baked goods, cookies, cakes, salads and game dishes. 
Hickory nuts are variable in size and shape. Borne 1 to 3 together, individual fruits are 3 to 6 cm long, oval to subglobose or obovoid, depressed at the apex, and enclosed in a thin husk developed from the floral involucre. The fruit ripens in September and October and seeds are dispersed from September through December.
Husks are green prior to maturity and turn brown to brownish black as they ripen. The husks become dry at maturity and split freely to the base into four valves along grooved sutures. The enclosed nut is light brownish white, oblong-ovate, somewhat compressed, usually prominently four-angled at the apex and rounded at the base. The shell is relatively thin and the kernel is sweet and edible. The bulk of the edible embryonic plant is cotyledonary tissue. 
A gloomy late October day has a shagbark decked out in butter-yellow fall foliage (spectacular in bright sunshine). Hickory nuts are a preferred food of squirrels and are eaten from the time fruits approach maturity in early August until the supply is gone. Hickory nuts also are 5 to 10 percent of the diet of eastern chipmunks. In addition to the mammals above, black bears, gray and red foxes, rabbits, and white-footed mice plus bird species such as mallards, wood ducks, bobwhites, and wild turkey utilize small amounts of hickory nuts. Hickory is not a preferred forage species and seldom is browsed by deer when the range is in good condition. Hickory foliage is browsed by livestock only when other food is scarce.
The bark texture and open irregular branching of shagbark hickory make it a good specimen tree for naturalistic landscapes on large sites. It is an important shade tree in previously wooded residential areas. At least one ornamental cultivar of shagbark hickory has been reported, but it is not planted as an ornamental to any great extent. The species normally contributes only a very small percentage of total biomass of a given forest stand. Its adaptability to a wide range of site conditions and vigorous sprouting when cut make shagbark a candidate for coppice fuel wood. However, difficulty in planting and generally slow growth makes shagbark less attractive than many faster growing species.
Shagbark hickory grows well in both dry and wet soil conditions, but prefers well-drained soils such as those found here, on a bluff overlooking the West Branch of the DuPage River in Northern Illinois. This bluff is the site of a Late Woodland period aboriginal settlement responsible for the effigy burial mounds at Winfield, Illinois.
Hickory has traditionally been very popular as a fuel wood and as a charcoal-producing wood. The general low percentage of hickory in the overstory of many privately owned woodlots is due in part to selective cutting of the hickory for fuel wood. Hickory fuel wood has a high heat value, burns evenly, and produces long-lasting steady heat; the charcoal gives food a hickory-smoked flavor. The wood of the true hickories is known for its strength, and no commercial species of wood is equal to it in combined strength, toughness, hardness, and stiffness. Hickory is used for furniture, flooring, and tool handles. The combined strength, hardness, and shock resistance make it suitable for many specialty products such as ladder rungs, dowels, and gymnastics equipment.
1. David L. Graney, USDA Forest Service Silvics Manual vol. 2 ‘Shagbark Hickory”
2. NATIONAL AUDUBON SOCIETY, National Audubon Society Field Guide to N. American Trees