Anyone dropping by my home in the late afternoon knows I treasure my two glasses of bourbon, poured “on the rocks” for a daily treat. My favorite at the moment is Jim Beam Black, which I am in agreement with magazine ads as the favored aged bourbon so described. Knob Creek has its cheerleaders, as does Makers Mark, and full-page photographs do these bottled whiskeys credit with their caramel-honeyed tones.
A recent article in American Forests describes why these esteemed bourbons are as good as they are, and it has to do with white oak barrels they are aged in for six years. By law since 1964, when Congress designated bourbon the national spirit of the United States, it also outlined criteria that bourbon must adhere to requiring aging in new, charred oak barrels.
The chosen species for that is white oak (Quercus alba) which does this job best. Even wine aged in a barrel does create a much more complex taste, and it is agreed by winemakers that the barrel-aging makes a big difference in quality. A year is the average in their process.
We are very cognizant of northern red oak being our oaken tree species in New Hampshire, as white oak peters out in the southern portion of our wooden state. That is a better wildlife tree with its acorns being more palatable, and Dave Anderson does a superb job in a recent Forest Society’s magazine on discussing the two for wildlife. White oak will germinate as soon as it hits the ground and wildlife must gobble it up immediately, while the red oak will wait a while before it does and wildlife such as squirrels can bury it for another day.
Anderson describes the tannins and chemistry the latter possesses which contribute to this longevity, but also make it harder to digest. He said the Indians used to soak the red oak acorns in black ash baskets sunk in streams for a while to help this along as a forage.
White oaks dominate the canopy from Missouri to Pennsylvania as the largest species by volume. The central hardwoods region is very Appalachian and very ecologically important for food sources, watershed health and climate mitigation.
White oaks are bountiful hard mast producers and can deliver 2,000 to 7,000 acorns per year. If you happen to have one large tree or a grove in the Lakes Region, you can expect deer grazing these up some morning and bears frequenting your property, too.
Even the odd, whitish, flaky bark is beneficial and a study in the Mid-Atlantic found white oaks can provide insect habitat here for more than 500 species of moths and butterflies. This is more than any other woody plants in this coastal region; from this perspective it is the most ecologically significant species in the eastern United States.
As white oaks can get huge, gaining impressive size and shape, this helps sequester carbon. The abundant deep roots and broad canopies play an important role in producing clean and steady streams of water, providing quality aquatic wildlife habitat for trout.
But back to the bourbon production. The American Hardwood Council declares that all of the sub-species of white oak together account for roughly one-third of the American hardwood resource. It is needed overseas, and white oak lumber exports increased by 24 percent up from $410 million in 2016 to $509 million in 2017. That much consumption is worrying foresters in this region as it is outstripping growth and white oaks’ seedlings are not appearing on the forest floor as they formerly did.
Like our forests up here, disturbance has a lot to do with species’ regeneration, and we are all experiencing the evolution of our forested landscapes recovering from past agrarian experiences and logging over 150 years plus. Shade-loving trees like the maples can replace the oaks.
White oak is an important economic resource across the eastern United States particular in rural areas where cooperage is such an art, and very hands-on. High-quality sawlogs are processed into barrel staves. Kentucky makes the most, and the state boasts that, with nearly one-third of $347 million of its wood products energy, or roughly $100 million, is the exported product of barrels.
White oak has tyloses, bubble-like structures in the heartwood that make the wood and products impenetrable to liquid and decay. We know that from building keels and transoms in wooden boats up here on the New England Seacoast. Careful selection and craftsmanship in the skilled coopers hands means that the barrels meet the whiskey distillers’ highest standards.
People handle every piece throughout the process. Defects in white oak are very random and hard to detect, so there is an enormous human element to the art. Time-tested, traditional techniques harken back to the era when these companies were founded five generations ago.
Dave Eastman also broadcasts “Country Ecology” four times weekly over WMWV 93.5 FM. As vice president of the Lakes Region Chapter/ASNH, he welcomes you to monthly programs at the Loon Center in Moultonborough. He is available at: firstname.lastname@example.org (or) countryecology.com for consultation.