114 INTRODUCTION TO BOTANY 



107. Problems of forestry. Most of the questions which 

 the practical forester has to consider can be grouped under 

 three heads: 



1. How to establish forests on areas naturally treeless or 

 on tracts of perfectly cleared land. 



2. How to maintain existing forests for an indefinite period 

 in the most productive condition. 



3. How to fell timber and remove it with the least possible 

 damage to the trees that are left standing. 



In a book on general elementary botany only a few hints 

 on these most important topics can be given. Every intelli- 

 gent citizen, however, should at least know that the conserva- 

 tion of our forests is highly essential, and should understand 

 the general bearing which it has on our welfare as a nation. 



108. Forest plantations on treeless land. In such treeless 

 regions as the prairies and the Great Plains it is often desir- 

 able to establish belts of timber or considerable tracts of wood- 

 land. This is done partly for shelter from winds and partly 

 for the timber produced for local uses. The seeds may be 

 planted where the trees are finally to stand, or young seed- 

 lings may be procured from a forest nursery. The latter plan 

 is the better, and it is well to have the young seedlings trans- 

 planted once or twice before their final planting, to avoid the 

 formation of long roots, the cutting off of which would check 

 the growth of the tree. Both coniferous and dicotyledonous 

 trees are much planted. Some of the most generally available 

 conifers are the white pine, the Scotch pine, the Austrian pine, 

 and several kinds of spruce. Among the desirable dicoty- 

 ledons are cottonwood (fig. 96), silver (or white) maple, 

 green ash, honey locust, hardy catalpa, red oak, and (in the 

 warmer parts of the country) eucalyptus. In climates such 

 as that of the lowlands of California, Eucalyptus globulus is 

 the most rapid growing of hard woods, reaching a diameter of 

 one foot and a height of one hundred twenty-five feet in ten 

 years. To reach this diameter the white oak would require 

 a hundred years. 



