Dale Kirby strides through the forest pushing back tree limbs and stepping over logs and the uneven ground with the nimbleness of someone well experienced in the outdoors. 

He pauses to survey a large, straight tree with white bark that stands out in stark contrast to other trees and the yellow, gold and red leaves of maples. “Yep, this is a good white oak here,” Kirby says, resting his palm on the tree. “You could get four, five barrels out of this tree.”

Kirby is walking his own stand of about 400 acres of timber near a state wildlife conservation area. The ground, covered with emerging trees and decaying timber, is still moist from a morning rainstorm that has also left the still, chilled air of a clear and cold fall day feeling fresh and crisp. “I have walked this forest since I was a kid,” Kirby says of the timber that he uses to supply his company, A&K Cooperage located in Higbee, Mo., which is a 45-minute drive north of the college town of Columbia, Mo., in the central part of Missouri.

A&K Cooperage is the primary barrel supplier for Silver Oak Cellars, which is based in California’s Napa Valley and also owns winemaking facilities in the Alexander Valley of Sonoma County.

Silver Oak, which makes 100,000 cases of wine per year, produces a popular, consistent Cabernet Sauvignon that is aged in American oak. The winery was so intent on maintaining a consistent supply of quality oak barrels that it bought a partner stake in the cooperage in 2000.

Kirby started the cooperage with his father-in-law D.L. Andrews more than 40 years ago. Today, the company makes about 5,000 barrels per year, with Silver Oak accounting for about half of that production. Kirby’s son Matt also works at the cooperage and said the oak business appears to have recovered from the recession. Sales are at the same level if not better than before 2009. “Demand is really good this year,” Matt Kirby says. “I don’t know what’s going on, but we’re working our butts off here.”

Next door to the Kirbys’ cooperage is Mid-West Stave Exchange, a stave mill owned by Robert Berendzen. Dale Kirby helped Berendzen set up shop. While the mill has been open for only six months, Kirby says, “People are beating down his door looking for wood.”

It is well known by winemakers how the quality of American oak barrels vastly improved during the past three decades. “When I first started making wine, American oak was green,” says Jeff Cohn, owner of JC Cellars in Oakland, Calif. “We used to wash those barrels as much as we could to get those harsh tannins out of them, but now they’re made very well.”

In addition to better milling and quality control, coopers refined their toasting techniques to provide a spectrum of flavors. Those in the barrel trade say they often stump winemakers in blind tastings of wines aged in French and American oak.

Yet while wine industry demand for American oak is up, many winemakers still only have a vague idea of the American oak forests being in the Midwest somewhere. Wines & Vines recently visited the oak forests of Missouri to gain better insights into the domestic oak industry.

In the forest
Barrels made with American white oak (Quercus alba) will likely always be cheaper than those made with the primary European oaks such as the sessile oak (Quercus petraea) and English oak (Quercus robur), because American oak contains more tyloses or large cells that make the wood watertight. Because more of these cells are present in American oak, logs can be quarter-sawn at the mill and more staves produced from one tree. European oak logs, however, must be carefully split by hand or powerful wedge presses along natural seams to ensure water tightness. In addition to the physical nature of the trees, the American white oak forest is vast, stretching across the central and eastern United States. American oak also contains different levels of flavor compounds and other wood materials that make it season and toast differently than European oak.

Kelly Frizzell is a logger and mill owner based near Salem, Mo. He regularly cuts trees for staves purchased by Salem Wood Products, which is owned by Independent Stave Co. (ISC), the parent company of the Napa, Calif.-based Cooperages 1912, which sells wine barrels under the World Cooperage, T.W. Boswell and Tonnellerie Quintessence brands. While the company is heavily invested in American oak, about 40% of the wine barrels Cooperages 1912 sells are made with French oak.

Frizzell is a fourth-generation logger who is certified through the Missouri Department of Conservation, which manages the state’s forests. He is also one of the state’s few “master loggers.” The certification required Frizzell to take classes that teach a specific way of cutting the trees as well as forest management. For Frizzell, a thick-framed man with a thick mustache who grew up in the woods and drops the “g” on words like hunting, it wasn’t easy to take a government class to learn how to cut trees. The certification, however, does mean his bids to cut state lands are awarded points that make them more competitive.

One damp October morning, Frizzell demonstrates making a hinge cut to fall a white oak. The process involves making a cut at an angle to the tree trunk, then boring into the trunk with the point of the saw blade before cutting across the width of the trunk. The technique helps Frizzell decide how and where the tree will fall to avoid damaging other trees in the forest or imperiling him and his crew. “The main thing about falling timber this way is you have control of the tree,” Frizzell says.

As Frizzell’s saw blade passes through it, the tree starts to list to the side where he cut the hinge and then accelerate before crashing to the forest floor. The area around the tree is soon redolent with vanilla and the spice of American oak, and the stump smells like the bunghole of a new American oak barrel that’s just been rinsed with hot water.

In the thick Missouri forests, white oak accounts for about 25% of the trees; red and black oaks, which are not suitable for wine barrels, make up 40% to 50% of the total trees.

Inspecting the base of the tree, however, Frizzell points out soft, rotted wood near the center of the trunk. He says the rot is scar tissue from fire damage. The area he’s standing in was once a sprawling pine forest that was clear cut in the late 1800s to provide fuel to a nearby iron ore smelting plant. Farmers would later burn the emerging trees to keep pasture clear for livestock. But left alone and given time, the trees came back.

The right trees for barrels
Loggers generally scout for straight trees with a diameter of 13 inches at the height of an average man’s chest. Staves are only cut from the lower section of a tree, so the best trees are the ones free of low-hanging branches or knots.

The tree that Frizzell has just cut may have survived fires, but if the scar tissue extends too far up the center of the tree, it may not be suitable for barrels and end up as railroad ties. It’s one of the challenges of the timber trade; loggers never know how good a tree is until it’s lying on the forest floor.

Using his homemade measuring stick, which is literally a wooden stick, Frizzell measures out the section he thinks could be cut for staves. The narrower parts of the tree will be used for other purposes. Because Frizzell owns his own mill, he has more options for the wood, but he admits the timber market is only just starting to rebound from the recession.

Cooperage wood accounts for just about 5% of the total market for white oak. But during the height of the recession, when the construction market collapsed, Frizzell said it was the stave business that kept him and other loggers afloat.

Most of the loggers in the area work in small operations of just two to three men who are often part of the same family. When logging private land, Frizzell said he would typically split the proceeds of a timber sale 50-50 with the landowner. He mentions that he’s been working with one property owner with several hundred acres of land who will cut enough oak each year to pay the property taxes.

One of the biggest challenges for loggers is accessing the trees and coping with the weather. Much of the timber forest in Missouri and other parts of mid-America is remote with little infrastructure. Heavy rains can make it impossible for crews to get into the forest and harvest oak trees. Forest access is actually a bigger constraint on the supply of quality oak than the size of the forests.

Because it’s often not possible for loggers just to cull out white oak trees, they need to wait for landowners to decide to cut swaths of timberland for all the lumber.

To overcome the terrain and conditions, loggers use large, heavy-duty tractors known as skidders to drag wood out of the forest, clear a path to the trees or winch logs up hills.

Buying and milling the wood
ISC doesn’t own any forests but instead relies on 16 log buyers scattered throughout Missouri, Ohio, Indiana, Kentucky, West Virginia and Tennessee to source logs for barrel staves. Most of that wood is destined to become barrels for the spirits industry. Wood for wine barrel staves mainly comes from the Ozarks region of southern Missouri and northern Arkansas.

The company currently operates three stave mills in the Missouri cities of Salem and New Florence as well as Salem, Ind. It will open a fourth stave mill in Morehead, Ky., by the end of 2014. ISC’s staves for wine barrels are sent to a sprawling cooperage in Lebanon, Mo. Spirit barrels also are made in Lebanon—but it is Lebanon, Ky., not Missouri. In addition to its U.S. operations, the company also owns and operates cooperages in France, Chile and Australia.

When loggers have timber for the stave mill, they truck the logs to the yard and spread them out for inspection by one of the company’s buyers. These hawk-eyed veterans quickly appraise the wood using ISC’s detailed criteria for stave logs. The wood must be the right species of oak and free of any defects that could produce unusable logs. Buyers measure the length and diameter and use the Doyle Scale, which accounts for the loss of total volume from sawing, to determine total board footage versus any visible flaws. A buyer will reject any log that contributes less than 70% usable wood. Reviewing 60 to 70 logs can take a skilled buyer just five to 10 minutes.

ISC has a comprehensive policy on what makes an acceptable piece of wood and the log defects that make timber unusable for staves. That doesn’t mean loggers don’t do their best to extol the qualities of their logs in the hopes of swaying a buyer or deliver the logs dirty in an attempt to cover up knots and other mars. “That’s why a lot of guys don’t like to sell logs in the rain, because all the defects show up,” says buyer Chad Cook.

It would be hard to pull one over on Cook, a veteran buyer who worked his way into the position from the sawmill floor. Cook, like most of his ISC colleagues, is paid by how well he meets his quality-control parameters. Every log Cook buys is tagged with a code, and that log is tracked through the milling process. If the logs Cook purchases don’t yield an ideal number of staves, Cook isn’t doing the best he can as a buyer.

View from Missouri is positive
In the Kirbys’ forest near Higbee, Dale Kirby explains that the cold winters are necessary for the tight growth rings of quality oak. He credits the region’s poor clay soils for causing a slow rate of growth that produces tight grain.

Trees on a north-facing slope tend to provide better wood for barrels because the trees see less sun. That results in tighter grain and straighter trunks as the trees reach for the sunlight.

Kirby says he’s been to Napa Valley at least 40 times and has a wine cellar from which he’ll pull special bottles for charity auctions. He says he’s heard the criticism of American oak, and as one might guess, it doesn’t mean much to him. “I don’t think anyone can tell you what’s good wine but you,” he says.

Daniel Baron, winemaker at Silver Oak Cellars, says the company first went with American oak to save money. Eventually, though, it became clear that the tannins in American oak integrated well, meaning the wines could be enjoyed soon after release yet still had the structure for aging. Now the wine is partly defined by its style, and Baron says he has no intention of changing the oak program.

Baron says American oak has a tradition with some of California’s other iconic brands: Andre Tchelistcheff at Beaulieu Vineyard used it in decades past, and it is still used by Ridge Vineyards. The winery’s 2010 vintage of its classic Monte Bello Cabernet Sauvignon received nearly 100% new American oak.

He says the company tried several different sources for barrels but ultimately determined that the best oak came from the area right around A&K Cooperage. To ensure consistency, Baron said the winery opted to buy a stake in the cooperage.

While A&K’s success was secured through Silver Oak, Dale Kirby says the cooperage has been able to build the business by adding other accounts. He says the company is now in a good position to expand its business, although he’s not sure how that will transpire.

The fact that large companies like World Cooperage and smaller coopers like A&K are confident about the future and looking to expand with the American wine industry is indicative of the increasing demand for American oak barrels.