PERIODICAL LITERATUKK -AGS 



The above tabulation emphasizes the fact that Scotch pine occupies 

 a by no means unimportant place in tree planting for forestry purposes 

 in Pennsylvania. In the reviewer's judgment, its use has been propor- 

 tionately great in many other Eastern States. 



Although Scotch pine is an important timber tree over its native 

 range in Europe, in the reviewer's judgment it does not prove that it 

 will do equally well in the United States. The forester is bold indeed 

 who advocates the extensive planting of this exotic species anywhere 

 in America. Professor Illick does an important service for Pennsyl- 

 vania in emphasizing the fact that the successful growth and develop- 

 ment of an introduced species depends primarily upon the closeness of 

 the correlation between the silvical requirements and the site factors 

 of the region where the trees are set out; also in discussing the pecu- 

 liarities and demands of Scotch pine, which is now being used quite 

 extensively in the United States in artificial regeneration. He points 

 out that this species, next to Norway spruce, has the greatest latitudinal 

 and altitudinal range of any of the European forest trees. He should, 

 however, have emphasized the fact that no forest stands of this species 

 have been brought to maturity in this country, and our judgment of 

 the excellency of the species for use in this country is entirely based 

 upon its juvenile growth. In the reviewer's judgment, the success al- 

 ready attained in securing admirable juvenile growth in plantations in 

 Pennsylvania and else\vhere in America is not indicative of what will 

 be the condition and yield of the stand at maturity. 



The juvenile growth of this species near Mt. Alto, Pennsylvania, is 

 excellent, as shown in the following table, which gives the annual height 

 growth up to II years of average trees on Quality I sites: 



Current height 

 Year Age of trees growth Total height 



(years) (inches) (inches) 



1907 I 2.0 2.0 



1908 2 3.0 5.0 



1909 3 3-2 8.2 



I9IO 4 4.0 12.2 



1911 5 6.4 18.6 



1912 6 13.5 32.1 



1913 7 18.2 50.3 



1914 8 23.3 73.6 



1915 9 25.9 99.5 



1916 10 30.6 130.1 



1917 II 31.9 162.0* 



• 1 3.5 feet. 



Contrasted with w hite pine on the same sites, Scotch pine at 1 1 years 

 of age averaged 13.5 feet in height, while white pine averaged but 9.2 

 feet. 



