The variety of oak-tree shapes is evident in the resourceful uses discovered for its many components. The bark, rich in tannins, was utilized to soften skins in the production of leather. Leaf galls, created by wasp larvae, provided a very dark ink that Leonardo da Vinci utilized in his sketches. Acorns, known as balanos in Greek, are depicted as phallic emblems in classical sculpture. In modern medicine, inflammation of the penis is referred to as balanitis.

Evergreen oaks in Spain are essential to the entire rural economy. Cork oaks, scientifically known as Quercus suber, undergo bark stripping every nine years. The acorns serve as sustenance for the nearby pigs. Branches from holm or live oak trees are pruned to boost the acorn yield. The trimmings are then turned into charcoal, which is sold for barbecuing. The roasted acorns from both species are sufficiently delicious to be a favored Iberian bar snack for humans, marketed as bellotas. The acorns of the South East Asian kunugi, a kind of Q. acutissima, are still actively traded for their starch content.

Modern Britons would not have traditionally used the very bitter acorns from their native oak trees, but during World War II, the Ministry of Food proposed creating a coffee substitute from them due to domestic shortages. The ingredients needed to undergo chopping, roasting, grinding, and a second round of roasting. The final drink was bitter and devoid of caffeine, making it unlikely for a nation facing a crisis to embrace it, either in their hearts or on their taste buds.

William Bryant Logan, who has a strong affinity for oak trees, was surprised by the common practice of using acorns as sustenance by humans. In 2004, while researching for his book “Oak: The Frame of Civilisation,” he discovered a chart showing the distribution of oak trees worldwide. He was surprised to see that the distribution of oak trees aligns with the areas of settled civilizations in Asia, Europe, and North America. Japanese and Korean traditions of consuming kunugi acorns were mirrored in North America, where indigenous peoples relied on white and live oak acorns for carbohydrates. It should not have been a significant shock. Most humans thrive in similar climatic and environmental conditions as most oak species. Logan was so affected by the coincidence that he developed a new theory regarding the beginnings of civilization.

He rejects the traditional notion that hunter-gatherers and early pastoralists transitioned slowly into cereal farmers by interacting closely with the wild grasses consumed by their semi-wild livestock. He advocates for an intermediate phase where acorns, collected and kept communally throughout winter, evolved into the universal model for centralized agriculture. People intentionally settled in areas where oak trees grew because they were seeking essential resources, not due to chance or similar ecological preferences.
Most archaeologists agree that late hunter-gatherers were collecting and storing nuts and fruit, possibly starting to cultivate them unintentionally when they discarded seeds and kernels.

The large oak tree at the edge of our garden in Norfolk serves as a concluding statement, a display of contrasting wooden elements that clearly signifies the limit of gardening. The canopy is 25 yards wide and consists of rugged, arching ribs with an algae-tinted hue. Being in its watery shadow seems like being within a huge stranded whale. Tawny owls, groups of fieldfares, ascending moons, the phrase I was contemplating while walking up to observe it, can disappear quickly in its wave of shimmering leaves. It took me a while before I could bring myself to measure the tree’s trunk using a tape measure. Approximately nine feet; perhaps less than a hundred years old.

That diminished its reputation, and for the first time in the decade I had lived with it, I viewed it solely as a building. I was surprised to see that my maze, which I thought was romantic, actually had a clear geometric structure. As I circled the trunk, I observed that the primary lateral branches, the largest ones, extended to the south at a height of ten feet and were perpendicular to each other. They all emerged from the stem at an angle of around forty-five degrees from the vertical.

Secondary branches emerged horizontally at a forty-five-degree angle below each slanting rib. It continued until the outermost twigs, alternating between upward and downward forty-five degree divisions. The ribs in the leaves were aligned at an angle to the central spine. I observed nine nearly identical angled forks on a single branch system between the trunk and leaf tip. Among all the oak trees in Norfolk, it appears that I have the one that follows the design principles of Pythagoras.