The big trees

   Almost everyone knows where there is a very big tree. It may be a maple tree or an elm or an oak. But trees like the big one in the picture grow to be far larger than any maple or elm or oak. They are true giants. One name for them is "big trees." Another name for them is "giant sequoias."
The biggest of the big trees are four or five times as tall as most of our shade trees. Their trunks may be as much as 30 feet across. There is enough wood in one of them for a whole village of houses.
   Many of the big trees now standing were living when Columbus discovered America. Some were living when Christ was born. Some were alive even back in the days of the Pyramids.
   Big trees are conifers. They bear their seeds in cones, just as pines, firs, and spruces do. Their closest relatives are the redwood trees.
   Giant sequoias are found only in parts of California. Most of them are in national forests. The men of the Forest Service guard them frorn forest fires, harmful insects, and tree diseases. If the big trees were not protected, there might soon be none left.