SILVICULTURE AND ARBORICULTURE 



257 



open and poor spots, and many of the trees may be weed 

 trees of no value in themselves and interfering with the 

 growth of useful trees. Some natural forests (as that shown 

 in Fig. 388) present a uniform and continuous stand of 

 timber of one kind; others (as in Fig. 387) are mixed forests. 

 Both kinds may be useful and desirable. 



432. Trees standing alone or on the edge of a forest do not 

 produce good timber because they branch too low and are 

 likely to be too much exposed to wind. They produce 



short and knotty 

 forest be thickly 

 and continu- 

 ously planted. 



433. Forests 

 may be planted 

 anew; or nat- 

 ural forests may 

 be perpetuated 

 by removal of 

 ripe and unde- 

 sirable trees and 

 the in-planting 

 or saving of 

 other trees. The 



logs. (Fig. 400.) It is essential that the 



433. A stand of young timber after moderate thinning. 



planting and rearing of trees in forests is silviculture. The 

 planting and rearing of trees in general is arboriculture, 

 and this may have no direct relation to forestry, because the 

 planting may be of lawn trees, park trees, roadside trees or 

 fruit trees. Silviculture is one part of forestry; other parts 

 or divisions are forest management, harvesting, marketing, 

 timber technology. The safeguarding and utilization of the 

 forests, both on public and private lands, is one of the great 

 public questions, and demands the attention of persons of 

 special training and skill. 



434. Forestry is an important farming question, for the 



