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Buffalo Trace’s Single Oak Project Explained

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The Buffalo Trace Single Oak Project was a massive undertaking by Buffalo Trace Distillery to find the perfect bourbon. Buffalo Trace Distillery’s goal was to determine how seven different factors affect the final outcome.

Those seven factors were:

  • Recipe (wheat or rye)
  • Entry proof (105 proof or 125 proof)
  • Stave seasoning (6 or 12 months)
    • Rough cut wood staves are left outdoors for a period of time to be naturally seasoned by weather.
  • Grain size (tight, average, or coarse grains)
    • Measured in rings per inch. 10 rings per inch signifies coarse to medium grain, 20 signifies extremely fine grain. Finer grain oak reduces leakage and can lead to a stronger, bolder taste.
  • Warehouse (concrete floor or wooden rick floor)
  • Char level (number three or number four char)
    • A number four char is pretty standard in the bourbon industry.
  • Tree cut (top or bottom half of the tree)
    • The bottom half of the tree contains more sugar. This leads to more caramels and flavoring in the finished product.


The project began in 1999 when former Buffalo Trace warehouse manager Ronnie Eddins made a trip to the Missouri Ozarks to hand select 96 American white oak trees. The project itself is dedicated to Ronnie for his over 40 years of service to Buffalo Trace. Many of the white oak trees from Missouri that were used for this project were over 150 years old; dating back to the Civil War.

Ronnie Eddins examining logs.
Ronnie Eddins examining logs.

These 96 trees produced two barrels each, totaling 192 barrels and 192 unique whiskies. Each barrel was created from a single oak tree. This in itself is quite an uncommon feat. Traditionally coopers carefully choose individual staves to complement one another and form a tight, uniform barrel. Having only a single half of a tree to choose from when creating each barrel must have been quite a challenge! Independent Stave Company coopers crafted the barrels used for the Single Oak Project. The very same coopers who make all of Buffalo Trace’s barrels and have been hand crafting bourbon barrels since 1951. (To learn more about these barrels, click

This was very much an interactive project between the distillery and both seasoned and amateur bourbon drinkers around the world. Individuals were offered the opportunity to request samples of these various bourbons in exchange for their feedback to Buffalo Trace. From the distillery, “In total, 5,645 people participated in the Single Oak Project which collected 5,086 unique whiskey reviews. On average, each of the 192 whiskies was evaluated 26.2 times.” Samplers were asked to answer 12 standardized questions about each bourbon they sampled. Evaluating based on color, aroma, mouth-feel, flavor, and finish. The 192 whiskies were slowly released to tasters over a four year period.

The winning bourbon came from barrel #80. It was a rye recipe bourbon, entered into a barrel harvested from the bottom half of the tree with staves seasoned for 12 months. The grain size of the wood was considered average and the barrel received a number four char inside. The whiskey entered the barrel at 125 proof and was aged in a concrete floor warehouse for eight years. However, finding the winning bourbon was not the sole product of this experiment. The 5,086 reviews provided Buffalo Trace with invaluable feedback on the 192 different bourbons. Cross referencing the reviews with the seven controlled factors mentioned above the distillery was able to glean some interesting information. Again a quote from Buffalo Trace, “For example, bourbons that produced the best aroma were made with a wheat recipe, entered at 105 proof, and aged in barrels whose staves seasoned for six months, in wood made from the bottom half of the tree. If flavor is your most important factor when picking a bourbon, then the research shows barrels made from the bottom half of the tree were a safer bet. And for those looking for the smoothest finish, a bourbon aged in barrels from (again!) the bottom half of the tree, but with a number three char and 9 tree growth rings per inch scored the highest.” This feedback should enable Buffalo Trace to produce even more interesting varieties of bourbon in future years.

Bottling Single Oak Project
Bottling Single Oak Project

For those of us who missed out of participating in this project there’s hope! The winning barrel #80 recipe will be produced in a future run to be released sometime in 2025 under the label “Single Oak Bourbon”. If you would like to try many of these bourbons today head over to
Fountainhead bar on Montrose in Chicago’s Ravenswood neighborhood. They are currently offering half ounce tastings for $5 with up to 22 varieties available (sadly number 80 is not among them).

Bourbon is America’s spirit, it’s distillation, aging, and bottling is strictly controlled. The process today is much the same as it was 150 years ago. Undertakings such as Buffalo Trace’s Single Oak Project are a welcome “innovation” to an age old system. This experiment has taught the distillery and the community much about how and why certain flavors come through in a finished bourbon. We applaud Buffalo Trace for undertaking this massive project and thank Ronnie Eddins for his work over many decades. We look forward to future releases especially the next Single Oak in 2025.