Tree of life: the iconic Celtic image likely depicts an oak tree, a food producer for animals and humans alike in protein-rich acorns. The tree of diversity: 450 to 600 species occur worldwide, depending on classification, as oaks easily hybridize. North America is an oak biodiversity hotspot with at least 220 species, the majority of which grow in Mexico. In Appalachia, about a dozen different oak species are found in various habitats.
These prominent trees have helped to shape culture, diet and ecosystems across the world, yet are facing significant threats to their ability to thrive. Today, oaks are struggling to regenerate, and diseases spreading in the West and Midwest could bring ecological devastation if they take root in Appalachia.
Let’s go back in time, to Los Angeles in 1875. Here’s what you see: basically nothing. The town—and “town” is even sort of grand for what it was—has about 8,000 people in it. But here’s something weirder: there are no palm trees. As a matter of fact, there aren’t really any trees at all. This area is just sort of a scrubland desert.
Over the next 50 years, palm trees would become a major transformative force in the development of Los Angeles. This is despite the fact that they don’t really do anything. The trees of urban Los Angeles do not provide shade or fruit or wood. They are lousy at preventing erosion. What they do, and what they did, is stranger: they became symbols.
More than a century ago, nearly 4 billion American chestnut trees were growing in the eastern U.S. They were among the largest, tallest, and fastest-growing trees. The wood was rot-resistant, straight-grained, and suitable for furniture, fencing, and building. The nuts fed billions of wildlife, people and their livestock. It was almost a perfect tree, that is, until a blight fungus killed it more than a century ago. The chestnut blight has been called the greatest ecological disaster to strike the world’s forests in all of history.
The American chestnut tree survived all adversaries for 40 million years, then disappeared within 40.
"Rocks and sediments bind up almost 98 percent of all nitrogen. The remaining 2 percent is in motion, part of a global chemical cycle that includes humans, bacteria, plants, and the atmosphere.
“Plants need nitrogen to grow,” says U.S. Forest Service research ecologist Steve McNulty. “However, excess nitrogen can harm plants.”
"Nitrogen and sulfur can combine with oxygen to form nitrogen or sulfur oxides. These compounds become part of the atmosphere, where they react with water vapor and other elements. Eventually, the nitrogen and sulfur – now in the form of nitric and sulfuric acid – fall to the ground with the rain drops."
"About three-quarters of tree species common to eastern American forests—including white oaks, sugar maples, and American hollies—have shifted their population center west since 1980. More than half of the species studied also moved northward during the same period."
"Local folklore has it that the tree grew when George Washington planted his walking stick while he and the Continental Army were encamped in nearby Newburgh during the final years of the Revolutionary War but core samples of the tree have dated its growth to 1699, well before American independence. Franklin Roosevelt often came to visit the tree."
The tree was cut down in 2015 when it was in terminal decline and ready to collapse on the road and surrounding houses. This summer though, the energy in the roots have allowed it to spring new branches and come back alive. While not uncommon for a large cut tree to do this, it's still a wonderful story of rebirth.