52 THE PLANT: A GENERAL EXTERNAL VIEW 



Have you ever noticed an asparagus bed in the summer ? 

 The old asparagus plants have numerous slender branches 

 which are green and do the work usually done by leaves. 

 The true leaves of asparagus are simply little brown scales. 



Uses of Stems to Man. — Apart from their value as being 

 necessary to the plant as a whole, the woody stems of 

 plants, especially the trunks of trees, are of great value 

 to man. Probably their first value to him was in affording 

 refuge. Fortunately for our remote ancestors, they were 

 better climbers than many of their enemies. 



The first rude huts were probably built of plant stems 

 and, even in this age of steel and concrete, the wood of 

 plant stems remains the most important material in the 

 building of houses. The furnishings of the house, as well 

 as most of the houses themselves, are made of it. You are 

 to learn of the method of nature in producing wood and 

 the principles which underlie proper care of the wood supply. 

 You have probably heard of forestry. Forestry is the art 

 of proper care and cultivation of the forests; it is im- 

 portant because the stems of trees are important. The 

 aim of forestry is to secure as much timber as possible 

 without injuring future timber production. Forestry is 

 based upon the science of plants. The government em- 

 ploys many foresters, all of whom must have a thorough 

 knowledge of the principles of plant life. 



Stems contribute to man's food and clothing as well as 

 to his shelter. Cane sugar comes from the stems of sugar 

 cane; maple sugar from the stems of maple trees. The 

 stems of asparagus, cauliflower, and cabbage are eaten; 

 of celery we eat the stem-like part of the leaf. The potato, 

 as you knoWj is part of an underground stem. Corn and 



