6 BULLETIN 871, IT. S. DEPARTMENT OF AGRICULTURE. 



Douglas fir predominates, the two pines take second place, and vice 

 versa. Third in order comes incense cedar, while sugar pine (Pinus 

 lambertiana) and white fir (Abies concolor) are but lightly represented. 



In the more dense stand on the lower slopes and in the draws 

 incense cedar forms a distinct understory, overtopped by all the other 

 species; it is in such localities that the cedar shows every indication 

 of slow growth and strong suppression. On the higher slopes and 

 along the ridges, where the stand is more open, the cedar in individual 

 cases often assumes a better position in the stand, and all the trees of 

 this species, with few exceptions, appear to be more thrifty and to 

 have made a more rapid growth. Badly suppressed trees are rare. 



The three areas selected to represent the optimum range are on 

 the Stanislaus National Forest in the southern Sierra Nevada Moun- 

 tains. One of these is at Strawberry, at an altitude of 5,300 to 5,600 

 feet; a second at Cow Creek, about 5 miles north and east of the 

 first and at about the same elevation; and the third at Crockers 

 Station, about 30 miles to the south and a little east of the Straw- 

 berry area and at an altitude of about 4,500 feet. Since the areas 

 are so nearly alike, a composite description will suffice. 



The soil is a rather deep, loose, decomposed granite, with many 

 large granite bowlders. It is normally somewhat dry. 



The virgin uneven-aged overmature stand is rather open and is 

 composed of sugar pine, western yellow pine, Jeffrey pine, white fir, 

 incense cedar, and Douglas fir. Normally the pines predominate, 

 with white fir or incense cedar next in order, Douglas fir being found 

 sparingly only on the Crocker area. Incense cedar is represented 

 by trees of all ages, and on the whole appears very thrifty. There 

 are many individuals of large size, comparatively young. The cedar 

 here is far from forming such a distinct understory as on the Sloat 

 area, so the stand has made a much more rapid growth. 



NOTES ON INDIVIDUAL TREES. 



After the general notes were completed on an area, work was 

 commenced on individual trees. Trees of all ages and conditions 

 must be cut for a study of this kind, the primary purpose being to 

 determine the age of the stand at which dry-rot becomes extensive. 

 Observations on logging operations and the results of Meinecke's 

 preliminary study had shown that trees between 100 and 240 years 

 old would yield the essential data on this point, and it was within 

 these age limits that the investigation was concentrated, but the 

 lower and higher ages were not neglected by any means. This 

 resulted in clear cutting within the ages mentioned, except that those 

 trees in which it was plainly apparent an accurate age count could 

 not be made were left standing, while only a portion of the trees in 

 the stand above and below these ages were cut. Thus, since a given 



