Today, horsetails are small. But millions of years ago, they were as
tall as trees.horsetails
The forests that turned to coal
The air was hot and wet. The ground was soft and oozy. Dragonflies with
wings as long as your arm hummed through the air. Cockroaches as big as
your fist hurried about. And, growing thickly everywhere, were strange
towering trees and other plants.
That’s what a forest was like during the Coal Age, 300 million years
ago.
We call it the Coal Age because the trees and plants that grew then
became the coal we use today. The plants in these forests grew and died
and fell down. They were quickly covered by other plants that died and
fell. All these dead plants were squeezed together. Slowly, during
millions of years, they became the coal some people burn for heat.
Some of the trees in the coal forests looked like Christmas trees.
Others were not like trees at all—they were strange, giant plants. One
of them was an ancient relative of the plant called a horsetail, which
grows near lakes and ponds. Today horsetails are only about 3 feet (1
meter) tall. But in the coal forests, they were more than 50 feet (15
meters) tall.
Use this small picture to find out the names of the plants in the big
picture.
