Missouri is home to 19 species and at least 16 hybrids of oaks. Most of our forest products industry, including flooring, barrel staves, pallets and railroad ties, is based on the oaks. Oaks are also the most important hardwoods in North America. Only three other species or groups of trees—all conifers—exceed them nationally in lumber production. Here in Missouri our oak saw timber volume of 8.3 billion board feet represents 63 percent of all our saw timber.
Much of our heritage and culture has been influenced by the oaks because of their unique qualities and sheer abundance. In ancient times humans not only admired but actually worshipped oaks. Ships and empires were built with oak. Oaks live, too, in legend and history: The old Oaken Bucket, the Charter Oak, and even in Robin Hood's Sherwood Forest.
Oak mast (acorns) is of tremendous importance to deer, squirrels, turkeys and other wildlife.
The oaks, which are related to beech, chestnut and chinquapin, have several distinguishing characteristics. The fruit is the familiar acorn, a staple food for many species of wild animals. Leaves occur singly on alternate sides of the twig. Large pores are found in the springwood and rays of wood radiate from the pith. Next to the acorn, the best identifying characteristic is the cluster or groups of buds found at the end of the twigs. The star-shaped pith of the twigs is characteristic also.
The larger family of oaks is divided into two groups. This aids greatly in identification by automatically eliminating the species in the other group.
The white oak group, called botanically Leucobalanus, is one group. In this the white oak, Quercus alba, is the predominant species. It also includes post, bur, swamp white, chinquapin, over cup, and swamp chestnut oak. These species provide the so-called sweet mast. Their acorns mature in one year, are less bitter, and germinate in the fall. Buds are rather rounded. The bark is light gray in color and rather flaky. Leaves are lobed or wavy along the edges but the lobes and ends of the leaf are rounded and smooth. The wood cells of these trees are coated inside with a plastic-like substance called tyloses. This makes the wood waterproof and accounts for its use in barrels, buckets, and ships. White oak wood is most durable.
Erythrobalanus is the name for the red or black oak group. This includes the true black oak, Quercus velutina, and also northern red, southern red, pin, shingle, willow, water, blackjack, cherrybark, shumard, and scarlet oaks. The live oaks are usually grouped here, too, although none grow in Missouri. Red oaks are characterized by the little bristles or spine-like tips at the end of their leaves or lobes. The leaves may be lobed or entire as in the case with shingle, willow and water oaks. Even in this latter case, bristles are at the tips of the leaves. Buds are pointed, bark is dark gray to black. It is rather rough and ridged rather than flaky. Acorns take two years to mature and they are bitter with tannin. They germinate in the spring. Red oak lumber is important for flooring and other uses, but it is neither very durable nor waterproof.
Red oaks have bristle-tipped lobes or teeth on their leaves, while white oaks lack this feature. The bark of red oaks is often dark gray, brown or occasionally black, and it is rough, hard and ridged. The bark of white oaks is a lighter color and scaly or flaky. White oak acorns are sweet and they mature on the tree in one growing season, while the acorns of red oaks are bitter and mature in two seasons.
The pores of the wood of the white oaks are plugged with material called tyloses. Because of tyloses white oak wood is used in barrels that hold liquids, and white oak is used in the aging of spirits like bourbon whiskey. Red oak barrels can only be used to store dry materials, and the wood has more important uses as railroad crossties and flooring.