FOREST PLANTING IN THE INTERMOUNTAIN REGION. 47 



snow disappears slowly in the early spring so that erosion and stream- 

 flow problems are of secondary importance. Here a brush cover of 

 good density is a satisfactory protection, and here also the establish- 

 ment of a satisfactory coniferous cover would prove most difficult. 

 With increasing altitude, summer storms become more violent, the 

 snow banks are deeper and melt more rapidly in the longer days of 

 early summer. This later water is of the most value to irrigation. 

 At high altitudes, therefore, especially within the Engelmann spruce 

 zone, coniferous cover becomes of great value, not so much as a soil 

 binder but as a means of reducing the rapidity of snow melting and 

 thus retarding run-off. Fortunately this is the very region where 

 artificial reforestation is most successful and where growth is fairly 

 rapid. The inauguration of such work depends primarily upon the 

 demonstration of its true monetary value, which has been very 

 difficult to determine. 



Such are the general conditions that will determine the future 

 resumption of forest planting in this region. Whatever the particular 

 conditions may be, the results of earlier planting work as shown in 

 this bulletin point unmistakably to the tact that problems in this 

 semiarid region are difficult indeed, and that general forest planting 

 which is not preceded by careful investigation and experimentation 

 on the contemplated planting sites is uncertain, if not predestined 

 to failure from the outset. The work already done has shown some- 

 thing of the general f avorability of the different classes of sites for the 

 different species. 



Future forest planting will probably be first concentrated on the 

 high mountain burns in the Engelmann spruce and lodgepole pine 

 types, where it will pay the highest returns, both in direct and indirect 

 benefits. From here it will extend downward into the Douglas fir 

 burns, inferior aspen areas, and temporary brush lands. Last of all, 

 the great permanent brush lands of the lower mountain slopes may 

 be considered for planting with conifers, together with other areas 

 lying on the border of potential forest land. 



SUMMARY. 



Reforestation by direct seeding is impracticable in the intermoun- 

 tain region. The planting of nursery-grown stock, on the other hand, 

 has been successful under favorable site conditions. 



The seed used in the nursery should have a high germinative energy 

 and should be collected from trees of good form and development 

 found in localities adjacent to the areas to be planted and having 

 similar soil and climatic conditions. 



The seedlings and transplants should be given sufficient water to 

 produce vigorous plants, but an excess should be avoided. Where 

 necessary, protection should be afforded against intense sunlight, 

 frost, and snow molding. Unusually heavy, calcareous clay soils 

 should be avoided for nursery purposes. 



It is essential that the young tree, in order to become established 

 when planted in the field, should be able to maintain a conservative 

 balance between water absorption and water loss through transpira- 

 tion. To accomplish this, the transplant must have a root system 

 sufficiently long to reach into the soil strata which retain available 



