FORESTRY LESSONS ON HOME WOODLANDS. 25 



Language: A survey of the general practice of home forest im- 

 provement of the district with a written report of the same will 

 afford a very good exercise in language. 



Geography : A district or county map locating the farm forest 

 areas and designating those under improvement. An outline map of 

 the State locating the farm forest areas. 



Lesson X. GROWTH OF TREES AND FORESTS. 



Problem. — To learn how trees and forests grow. 



Sources of information. — Farmers' Bulletins 134, 173, and 1071; 

 Forestry Bulletin 92 ; Department Bulletin 308. 



Illustrative material. — Potted seedlings, pots or boxes, and seeds 

 of trees. A chart showing roots, stem, and leaves of a tree. A chart, 

 or better, an actual, cross section of a tree stem showing different 

 parts of the stem, such as annual rings, heartwood, sapwood, bark, 

 and cambium. Leaves mounted so that their structure can be 

 studied. Branches showing bud and twig arrangement. Drawings 

 showing shapes of crowns of trees grown in the open and grown in 

 close stands. 



Topics for study. — The life of a tree and why it is necessary to 

 know something about how trees live. 



The leaves, trunk, and roots, and function of each in the tree's 

 existence. How the tree breathes and gets its food from the soil 

 and air; what travels upward and what downward in the branches 

 and stems. Structure of the leaf and different parts of the trunk. 



How the branches lengthen and the tree trunk increases in size; 

 the location, color, and structure of the living tissue or cambium 

 layer. What are annual rings, heartwood, and sapwood? 



Requirements for growth: Air, light, moisture, and heat. 



Trees in association — a stand. Influence of trees upon each other. 

 Difference, if any, between shape of crowns of open-grown trees and 

 those grown in close stands. Influence of different light and soil 

 moisture supply. 



Effect of tree density (number of trees in a given area) upon 

 growth of the individual tree. Natural dying out of trees in close 

 stands with advancing age. Understocked, well-stocked, and over- 

 stocked stands and the production of (a) saw timber, and (5) cord- 

 wood per acre under each condition. 



Practical exercises. — Make the following tests to show require- 

 ments for growth. Place a potted forest tree seedling in the dark 

 for a few days; withdraw moisture from one and supply moderate 

 amounts of moisture and excess moisture to other seedlings; sub- 

 ject plants, if possible, to different degrees of heat. Note results. 

 Erect a pole or 1 by 2 inch timber strip close beside a young, thrifty 



