A Guide to the Various Oaks Growing in Missouri
Oaks are unique in many ways, but most strikingly is how well oaks represent the classic stereotype of a tree. Most everyone has had an experience with oaks, be that collecting the acorns that litter the ground or climbing on their large, low-hanging branches as children; or raking their leaves off the street come fall time. Oaks tend to be large, with the largest oaks growing up to 100 feet high and can a trunk diameter of up to six feet. Even more impressive, though, is the width of the oaks’ canopy, which can be up to twice the size of the tree’s height. Oaks are deciduous trees, meaning their leaves drop come fall, leaving a looming skeletal figure in place of the once lively canopy. Additionally, oaks account for the highest lumber production of any hardwood tree, being beaten out only by three other species of conifers (softwoods).
Pictured below is a photo displaying the sheer width of an oak’s canopy.
History of Human Use of Oaks
Oaks, classified in the genus Quercus, have an approximated 600 species across the world, 56 of which are native to North America, and 21 of which are native in Missouri . Oaks have been supplying us with hearty wood for centuries; however, lesser known is that acorns and the bark of oaks have been used to treat inflammation and diarrhea. Additionally, early Europeans and Americans would make flour for baking by grinding down acorns . However, extensive use of oaks did not start until the 1500s, when the Spanish discovered oak’s superiority in ship building. Many of the species used to cross the Atlantic Ocean to the new world were made out of oak. Demand for oaks reached an all time high during the shipbuilding golden ages of the late 1700s to mid 1800s in both the US and Europe. In fact, some oak species were so popular, that this demand decimated their populations globally . Nowadays, the oak wood is still widely used, particularly in hardwood floors, but more interestingly: in bourbon/whiskey barrels. White Oaks are used extensively in the whiskey making process, and the interaction between the wood and the alcohol is part of what gives each type of whiskey its unique flavor. In fact, a common saying is: whiskey without an oak barrel is just moonshine!
Oaks belong to the genus Quercus and there are two distinct groups within the genus: White Oaks and Red (or black) Oaks. While obviously different, both groups have some key similarities. Both types of trees reproduce the same way. Oaks are hermaphroditic, meaning they have both male and female flowers on the same tree. Pollination of these flowers occurs by wind; female flowers will only open once the male flowers on the same tree have dispersed all their pollen . This action is to promote cross breeding (and prevent self pollination), and is partially why oaks hybridize so easily. The fruit of the tree, acorns, can take one to two years to reach maturity depending on the type of tree. Acorns are a staple in the diet of many wild animals, and therefore will only occasionally have the opportunity to grow into a new tree. Additionally, oaks hybridize with ease, meaning that one species of oak can cross pollinate with another, and grow a hybrid mix of the two trees. Unlike most hybrids, oak hybrids are “viable,” and can reproduce on their own. Because of this, identification of oak trees is much less straightforward than for other genuses as extensive variation can happen from tree to tree of the same species.
Similarities aside, there are a couple of distinguishing features between these two types of oaks. These differences are apparent in the leaves, acorns, bark, and even the wood of the tree.
- White Oaks have lobed leaves that are not serrated, while Red (or black) Oaks have bristle-tipped leaves. This is the most distinct feature between the two families of trees.
- The bark of White Oaks tends to be lighter in color while the bark of Red Oaks varies from a dark grey to brown.
- For a significantly harder to see distinction: the acorns of White Oaks reach maturity after one year, while those of Red Oaks reach maturity after two years. Additionally, the acorns of Red Oaks have hairs on the insides of their cups, while White Oak acorns do not.
- Lastly, the timber of the Oak varies greatly between Red and White Oaks. The Red Oak wood is quite porous and has a reddish tinge while White Oak is leakproof and has a lighter look to it.
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