216 JOURNAL OF FORESTRY 



Pinon grows very slowly throughout its life. The rate of diameter 

 growth, however, seems to increase with age until the tree reaches 

 merchantable size. The height growth increases at first, but after about 

 40 years appears to remain about constant until well over 100 years, 

 when it begins to fall ofif. 



Like all species accustomed to arid conditions, pinon grows far more 

 rapidly on sites supplied with a deeper soil, capable of storing moisture, 

 than on rocky, dry sites. Its responses to cultivation, as shown in the 

 arboretum at the Fort Bayard Nursery, is remarkable ; yet it must be 

 classed as a slow grower, and its value, in comparison with the more 

 important timber trees, rests chiefly on its ability to resist extremes of 

 transpiration caused by drouth, heat, and wind, which render the grow- 

 ing of yellow pine impossible. Were it not for the pifion and the 

 juniper species, the range of our woody vegetation throughout the West 

 would shrink perhaps one-half, and a supply of cordwood, now easily 

 accessible and of good quality, would be lacking. 



The rate of growth of juniper probably does not exceed that of pinon. 

 As an offset to this slowness of development we must remember that 

 most of the land on which these species grow is non-irrigable, rough, 

 and utterly worthless for agriculture. The cost of administering such 

 areas is low, fire protection is not a serious problem, and the revenue 

 from grazing can be made to carry all the expenses of administration. 



Reproduction is usually sufficient to replace the stand, especially if 

 a diameter limit is placed upon the trees to be removed coincident with 

 the production of prop sizes, or, in the case of juniper, of 10 to 12 

 inches on the stump. The retention and management of this type 

 within National Forests may not yield a large revenue per acre in the 

 long run, but what it does yield is almost clear profit. The product, 

 cordwood and mining timbers, will always be in demand, and in sea- 

 sons like the present, where coal shortages are threatened, local com- 

 munities may be forced to depend largely on this type for fire-wood. 



The forest values of the pifion and juniper abundantly justify the 

 retention and management of the type. 



