Phyllis Drake, age 9, of Lancaster, Pa., for her question:

How were the first trees started long ago?

The story of the oak, the elm, the ash and the giant redwood started long, long ago when our earth was very young. Maybe no more than a billion years old. The flaming gases of her babyhood had cooled to form a solid crust. Scalding rains had collected in shallow pools to form the ancient seas. And in these warm waters, rich in chemicals, the first living things had their beginnings.

Almost surely they were plants. For even the tiniest animals feed on plants or on other animals that feed on plants. So animals could not appear till there was plant life for them to eat. The first plants teemed in the early seas, much as the tiny algae still teem in our lakes and rivers. Maybe they were even smaller than the blue green and red algae that tint our streams and ponds, Twenty five thousand of these little plants measure one inch,

Life in the early seas was kind to earth’s first living things. They fed and multiplied. In time some of them became bigger and more complicated. Tiny seaweeds drifted on the tides. And many billions of them perished helplessly as they were beached on the hard, dry land.

As time went on, the plants grew bigger, more complex and better able to take care of themselves. Some were able to hoard water for the dry spells on the beaches. Then, about G billion years ago, a few of them bravely set down their `roots and came to live forever upon the dry land. Gradually they spread, taking different shapes and sizes, until they covered almost the whole world in a mantle of green,

Some found themsleves in dry sandy climates. Only those that could hoard water survived. Their descendants are our cactuses. Some along to damp spots in all sorts of climates and did not change much; much through the millions of years: They are the mosses;

Through the long, long ages, all the plants became more and more complex# Two hundred and fifty million years ago, vast swampy areas were covered with lush forests of strange looking ferns and horsetails.

Many of them left the prints of their ferny fronds as they formed our beds of coal. The first large trees as we know them probably came upon the scene about two hundred million years ago. Like all the plants we know, they were descended from the very first living things to come out of the ancient seas and make their homes upon the dry land. Most likely these first trees were conifers  .  the ancestors of our cone bearing pines, larches and giant redwoods,