It’s easy to take trees for granted, these stationary beings so numerous all around us, so lacking in animation; these wooden characters who conduct their affairs, as planetary scientist and polymath Carl Sagan observed, with such “astonishing slowness.”
Yet these quiet organisms have played a profound role, perhaps a leading one, in the rise of humanity to its present lofty and precarious position. It is a little understood fact that throughout history civilizations have risen — and fallen — largely based on how they treated or mistreated their forests.
The Romans built their expansive empire largely through their ability to assemble mighty ships that enabled conquest militarily and in oceangoing trade. The lime kilns that produced the concrete that Rome used to construct aqueducts to water her cities and to build the Colosseum required vast quantities of wood for charcoal: It was the black gold of its day, providing industrial-intensity heat to fire pottery, brick and tile, and to smelt copper, silver, and iron.
Earlier, the Greeks built a classical civilization in large part with the wood that allowed them to smelt glass and build their temples, boats and barges, spears, bows and arrows, chariots and catapults, stockades and breastworks, water wheels, looms, barrel staves and casks for brewers and vintners, and maybe even Trojan horses.
What a remarkable thing wood was — and is — a renewable, living substance that can serve as a light, strong, and beautiful building material. A strategic resource for ancient empires when used to make tall ships’ masts and long, strong hull planks, and one that doubles as an energy source.
In those countries the tall, cool forests and deep soils are long gone, expended in the climb to greatness. As history has shown, when wood shortages triggered trade imbalances with other lands, then timber raids and resource wars, eventually the countries with the more abundant forests rose to dominance.
We can recognize the natural services that forests provide today but they are under-appreciated.
First and foremost woodlands are water factories — they capture, purify, store, and release water used by ecosystems, farms and cities.
Forests help cleanse the air and dampen noise. They boost soil productivity, not only with the nutrients laid down in rotting leaves, limbs, and trunks, but also in loosening the soil with their roots, allowing the intake of air, water and beneficial microorganisms.
Forests moderate climate by capturing and storing carbon in their vegetation and soils. And they are estimated to house some 80 percent of the world’s terrestrial plant and animal species, making them essential storehouses for biodiversity.
Perhaps less tangibly, forests provide priceless recreational and spiritual values, as well as the economic values of tourism, recreation and retirement. Quality of life is a fundamental economic asset to any community.
When ancient civilizations destroyed their forests they not only took down their greatest strategic asset but also filled harbors with silt, necessitating expensive dredging operations. They created plains of silt, which bred mosquitoes and enabled typhus to deal nearby populations a fatal blow. The mineral salts flushed down from denuded watersheds salinated and sterilized irrigated cropland. Even the coins of the realm, in the face of shortages of charcoal for smelting, have been found in the archaeological record to contain more alloy and less base metal than during times when forests were plentiful.
Wise counselors back then were cognizant of the value of forests. Said Cicero of Servilius Rullus, a tribune who planned to sell an important state forest to the private sector: “He is a luxurious rake who would sell his forest before his vineyards.”
As for oak forests and woodlands, the predominant sylvan scene in Napa County, the ecological services enumerated above hold true — just with a good deal more golden sunlight filtering down through a more-open canopy to the grasses and forbs below.
Harvard biologist Edward O. Wilson, in his “biophilia” hypothesis, suggests that our affinity for savannas may run especially deep—deeper than for closed-canopy coniferous and broadleaf forests. That’s because savannas — not unlike the iconic oak savannas of California’s coastal ranges and foothills— made up the early East African environment in which we evolved to our modern form.
Although modern civilization no longer relies on forests for making strategic ships, or for smelting, or for virtually any of our most-essential implements, it is apparent that even in today’s industrial-technical society we need forests even more than did the ancients, for three big reasons: 1) for biodiversity, the source of unique genetic analogs for making pharmaceuticals, foods and fuels, 2) for carbon sequestration against the tide of global warming, a specter that threatens civilization itself if left unchecked, and 3) for large-scale, cost-free water purification and storage.
Sagan set things straight about the downright dependence we have on our vegetable cousins: “What a marvelous cooperative arrangement — plants and animals using each other’s waste gases. But there would be carbon dioxide in the air even if there were no animals. We need the plants much more than they need us.”