Trees Are Overrated


Preserving the world’s great expanses of grass could be essential to combatting climate change.

***Winner of the 2023 Science Writing Award from the American Society of Journalists and Authors***

Grasslands are overlooked and undervalued, but they have much to offer. (Credit: PxHere)

Once upon a time, not a blade of grass could be found on this planet we call home. There were no verdant meadows, no golden prairies, no sunbaked savannas, and certainly no lawns. Only in the past 80 million years—long after the appearance of mosses, trees, and flowers—did the first shoots of grass emerge. We know this in part because a dinosaur ate some, and its fossilized poop forever memorialized the plant’s arrival.

Grass then was still an odd little weed, vying for a spot on the forest floor. It took ages for grasses to grow in numbers that might constitute a grassland. And grasslands only started to occupy serious real estate in the past 10 million years—basically yesterday. They now cover roughly one-third of Earth’s land area.

We humans arrived in the midst of grass’s heyday, and it is doubtful we would exist otherwise. Homo sapiens evolved in and around the savannas of Africa, then spread around the world, often following grassy corridors. With the invention of agriculture, many societies fed themselves on domesticated grasses like wheat and corn, and on livestock that turned wild grasses into edible protein. We are, many of us, grass people.

But for all grass has done for us, we haven’t done much for grass lately. Grasslands rank among the most imperiled and least protected biomes on Earth. They are disappearing even faster than forests, and much of what remains has suffered varying degrees of damage. Their decline threatens a huge chunk of the planet’s biodiversity, the livelihoods of roughly 1 billion people, and countless ecological services such as carbon and water storage. Yet these losses don’t register with the same force as deforestation. Perhaps because we do not notice, or perhaps because we do not care.

The tendency to overlook and undervalue grasslands is a product of their reputation as degraded and thus disposable landscapes—a misperception rooted in centuries of scientific confusion and cultural bias. It reflects a deeply held preference for forests, mainly among people of European descent, that has warped global grassland science and policy. Scholars have described the problem as “arboreal chauvinism” and the “tyranny of trees.”

Read the full story in The Atlantic. You can also listen to me talk grass with Aaron Scott on NPR’s Short Wave podcast, and with Boyce Upholt on the re: Wild podcast.