IX. OUR FORESTS, THEIR USES AND THE NECES- 

 SITY FOR THEIR PROTECTION 



Problem.— Man's relations to forests. 



(a) What is the value of forests to man ? 



Qj) What can man do to prevent forest destruction ? 



Laboratory Suggestions 



Demonstration of some uses of wood. — Optional exercise on structure 

 of wood. Method of cutting determined by examination. Home work 

 on study of furniture, trim, etc. 



Visit to Museum to study some economic uses of wood. 



Visit to Museum or field trip to learn some common trees. 



To the Teacher. — The practical value of work on forestry is unquestioned. 

 Every pupil of high school age should have not only some knowledge of our forests 

 and their uses, but also a little first-hand experience in recognition of some common 

 trees : their habitat and their use. The methods of cutting lumber and trim also 

 gives a practical side which is of interest to pupils. 



Problem 80: To determine how lumber is cut and how to 

 recognize the cut in trim. 



Materials. — Diagrams, school furniture, Hough's sections of 

 woods. 



Method. — Examine the sections shown you. Compare with 

 lower figure, page 111, Civic Biology. 



NOTE. — Most lumber is cut tangentially. Hence the yearly rings take a more 

 or less irregular course. The grain of wood is caused by the fibers not taking 

 straight lines in their course in the tree trunk. In many cases the fibers of the 

 wood take a spiral course up the trunk, or they may wave outward to form little 

 projections. Boards cut out of such a piece of wood will show the effect seen in 

 many of the school desks, where the annual ring$ appear to form small elliptical 

 markings. 



Study the top of your desk, the wainscoting, the floor, and any 

 other wood at hand to determine the kind of cutting. Study 



96 





