FORESTRY LESSONS ON HOME WOODLANDS 



15 



stocked stands and the production of (a) saw timber and (b) 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 

 sapling pine or hardwood. At regular intervals of a week or month, 

 mark on it the total height of the growing tree. Keep a record also 

 of the dates and measured heights. 



Figure 9. — Effect of light supply upon the form and commercial value of trees. A, Elm 

 which grew up among other trees of the same height but since cut down. Clear 

 trunks make valuable lumber. B, This elm grew standing in the open. Trees with 

 short limby trunks are useful chiefly as firewood 



Topic V. FOREST REPRODUCTION 



Aim. — To teach how trees reproduce themselves. 



Sources of information. — Farmers' Bulletins 173 and 1177. 



Illustrative material. — Make a collection of seed specimens of the 

 classes indicated under "Guides to study." Either mount these 

 seeds on cardboard or put them in wide-mouth bottles. Clip pictures 

 of young forest growth. 



Guides to study. — Seeds: The various devices of nature for dis- 

 persing the seed widely. Tree fruits with (a) wings, plumes, etc. ; 

 (b) pulpy fruit with bony seeds sought by birds ; (c) rich nut kernels 

 liked by rodents and birds, and often buried or otherwise stored 

 away; (d) light seeds which float or roll along the bottom of 

 streams. Species of trees whose seeds are (a) carried by wind, (b) 

 water, or by (c) birds and animals. (Fig. 11.) 



