18 



clining in use, while the conifers are increasing. (Scotch pine alone 

 covers a larger area than all the broadleaf species together.) 



THEIR PROTECTIVE VALUE. 



To be of commercial value a species must possess adaptability, use- 

 fulness, and rapidity of growth. These should have foremost con- 

 sideration even when planting is done mainly for protection, as in 

 the region embraced by this report. Here protective planting is 

 so absolutely essential that groves of deciduous species of little com- 

 mercial value, which afford shelter only during summer, have been 

 valued at $1,000 an acre. Surely, then, conifers, which are more valu- 

 able commercially, and which afford protection during winter when 

 there is most need for it, should be worth a slightly higher price and 

 the extra care necessary in securing a satisfactory stand. 



Conifers are sometimes objected to on account of a possible yellow- 

 ing of the leaves. This is reported as occurring during hard, open 

 winters, with occasional warm, sunny days. On the warm days the 

 leaves become active and transpire water at a time when the frost- 

 bound soil can not supply the loss, hence the drying or " yellowing." 

 This trouble is experienced mostly with trees that have no protection 

 whatever against the sudden changes of heat and cold. Deep-rooted 

 trees like Scotch and western yellow pine, etc., should be planted in 

 preference to shallow-rooted kinds. They should be planted in dense 

 stands, so that they can prevent deep freezing of the soil and protect 

 each other from such midwinter stimulation. While loss from this 

 source is occasionally recorded no evidence of its occurring could be 

 seen during the investigation. Table 2 shows the number of living 

 trees per acre for 4 species and 5 groves. 



TABLE 2. Number of living conifers per acre in five plantations. 



So far the main objection to the general planting of conifers has 

 been the excessive cost of the planting material. Experience, how- 

 ever, has proved that coniferous stock can be grown in quantity at a 

 cost which does not make its use prohibitive. 



SCOTCH PINE. 



Scotch pine is native to the mountains of Europe. It was probably 

 first recognized in Scotland as a tree suitable for cultivation, hence 

 the name "Scotch" pine. It is a large, long-lived tree, reaching a 



[Cir. 145] 



