REFORESTATION ON THE NATIONAL FORESTS. 61 



periods of extreme drought may occur at any time between April 

 and November. Such a condition inevitably means a large degree 

 of failure in new plantations. Rodents also cause heavy loss, but 

 indications are that spring planting, use of large stock, or planting 

 on an area immediately after it has been burned will minimize the 

 rodent danger. Shade is of extreme importance, since it assists in 

 preserving soil moisture. 



Western yellow pine has been most successfully used between 3,500 

 and 5,500 feet elevation. The highest degree of success is attained 

 under full brush shade, and a classification of planting sites may be 

 made largely upon the basis of the shade characteristics of the brush 

 species. The most favorable brush types are as follows, arranged in 

 the order of their value: 



1. Manzanita and snowbrush type. 



2. White thorn and manzanita type. 



These types are generally found at elevations over 4,000 feet. The 

 oak and open-brush types found at lower elevations are more difficult 

 sites, in which success can only be obtained in very favorable years. 



Washington and Oregon, 

 douglas fib. 



1. Areas covered with a dense growth of herbaceous vegetation in 

 which fern usually predominates, indicating good soil and moisture 

 conditions, mostly on the west side of the Cascades and in the Coast 

 region at altitudes below 2,500 feet ; in the Coast region of the Siski- 

 you Mountains at elevations under 1,500 feet. The north slopes are 

 the best. 



2. Slopes covered with a medium growth of herbaceous vegetation 

 indicating fair soil and moisture conditions, second only to class 1; 

 mostly on the west side of the Cascades and in the Coast region be- 

 low 3,000 feet; in the Coast region of the Siskiyou Mountains be- 

 tween altitudes of 1,500 and 5,000 feet. 



3. Sites between 3,000 and 4,500 feet in altitude on east and west 

 slopes of Cascade Mountains. On these sites the soil may be thin and 

 rocky, but the moisture conditions are usually good. Douglas fir 

 should be planted in mixture with noble fir on the west side of the 

 Cascades, and with western white pine or Amabilis fir on the east 

 side. 



4. North slopes at moderate altitudes in the Blue-Mountain region, 

 typically cool and moist. 



5. Areas below 3,000 feet on the west side of the Cascade Mountains 

 and in the Coast region with only a scant ground cover, indicating a 

 dry exposed situation. 



