INTRODUCTION XXXI 



years we have been rapidly reducing our area of virgin forests, so 

 that a large part of that which remains has been partly cut or 

 burned over. It is estimated by the U. S. Forest Service that of 

 our total forest area, 200 million acres are as yet unlumbered; 

 250 million acres have been partly lumbered or burned over but 

 are restocking naturally with young growth; 100 million acres 

 formerly in merchantable forest have no young growth, or else 

 it is too scanty to develop into a merchantable stand of timber. 

 This vast area, practically valueless for agricultural purposes and 

 without young growth, can be restocked by seeding and planting. 



9. SEEDING AND PLANTING 



Extensive afforestation and reforestation must eventually be- 

 come an important part of forestry in the United States. Afforest- 

 ation, however, should be regarded as a business belonging to the 

 nation and state rather than to the individual. In the prairie 

 regions, however, and to a lesser extent in other parts of the West 

 where agriculture is possible, afforestation has been in the past, 

 and will continue to be in the future, a distinct field for individual 

 effort. Up to the present time the most successful attempts at 

 afforestation have been on the prairie farms of the West where 

 catalpa, locust, mulberry, Osage orange, elm, ash, and cotton- 

 wood have been grown under short rotation for local purposes. 

 In the more strictly arid regions of the Southwest, namely, in 

 California and Arizona, successful afforestation has been attained 

 over limited areas by planting various species of the exotic genus 

 Eucalyptus. 



The high cost and difficulties experienced in attaining suc- 

 cessful afforestation make it imperative that the work be ap- 

 proached with conservatism and mature judgment. Over much 

 of the non-agricultural region of the West the possibility of suc- 

 cessful afforestation can be determined only by long and careful 

 experiments. It does not necessarily follow that trees planted 

 on forestal lines will succeed because single specimens of the same 

 species thrive. Under adverse conditions for tree growth, nearly 

 all species appear to do better when planted as single specimens 

 than when grown in forest stands. The natural tree growth on 

 the arid foothills and high mesas of the Southwest is always in 

 very open stands. Each tree is sufficiently distant from its 

 neighbors to give it practically the condition of growing alone. 



