FORESTRY 345 



Every branch starts at the center of the tree; no 



matter how old it is, you can always follow it clear in 

 to the center when you split the trunk open. Sometimes 

 you find that it sends out small branches inside the 

 trunk. This makes the kind of wood seen in bird's- 

 eye maple and curly redwood. 



Every visit to the wood pile teaches something new 

 and interesting. Notice how the bark looks under each 

 small branch; can you explain how rings are formed 

 which you see on the outside of the bark ? What hap- 

 pens to small branches which are broken off close to 

 the trunk? Why does a knot in a board fall out and 

 leave a knothole? 



Each kind of wood has its use. Find out the uses 

 of the common woods and why they are so used. 



What causes the warping of wood? How can it be 

 prevented? If a dry board is placed in water, does it 

 swell just as much with the grain as across the grain? 

 Draw a square ten inches each way on a dry board and 

 keep it under water for a week; then measure the 

 square. How much larger is it? Is it still a square? 



There is much good information about trees and 

 forests in Pinchot's " Primer of Forestry/' Roth's 

 " First Book of Forestry/ 7 and Hodge's " Nature Study 

 and Life," Chapters 22 and 23. 



