Scientists have unearthed evidence in New York of the world’s oldest forest, dating back nearly 400 million years.

The fossilized forest, which is 386 million years old, was discovered in a quarry in the upstate town of Cairo, around 33 miles south of Albany, according to a new study.

The discovery was reported in the latest issue of Current Biology and is believed to be 3 million years older than the previous world record holder, which is located around 25 miles away in Gilboa.

Researchers said the recent findings provide new insight into the evolution of forests, indicating that the Earth’s transition to them began 10 million years before trees started growing from seeds.

“We are really getting a handle on the transition of the Earth to a forested planet,” said study co-author Dr. Chris Berry of Cardiff University in the UK.

Researchers believe the forest was home to a wide-ranging network of trees that reproduced using spores, rather than seeds, as well as a rich array of vegetation that was eventually wiped out by a flood.

“It is surprising to see plants which were previously thought to have had mutually exclusive habitat preferences growing together on the ancient Catskill delta,” said Berry.

The forest was inhabited by two different species of trees — primitive fern-like plants known as cladoxylopsids and Archaeopteris, which are characterized by their woody trunks and frond-like branches.

“This would have looked like a fairly open forest with small to moderate-sized coniferous-looking trees with individual and clumped tree-fern-like plants of possibly smaller size growing between them,” Berry said.

The study also identified “spectacular” woody roots that belonged to the Archaeopteris. The roots contained multiple levels of branching and small, short-lived perpendicular feeder roots, which researchers credit with transforming the interaction of plants and soils.

“In order to really understand how trees began to draw down carbon dioxide from the atmosphere, we need to understand the ecology and habitats of the very earliest forests, and their rooting systems,” Berry said.

Binghamton University Professor William Stein, the study’s lead author, said the team plans to continue looking at the Catskill region and compare their findings with fossil forests around the world.

“It seems to me, worldwide, many of these kinds of environments are preserved in fossil soils,” he said. “And I’d like to know what happened historically, not just in the Catskills, but everywhere.”