36 NORTH A:\rERICAN FAUNA. [no. 16. 



(2) The Middle Belt or Belt of Shasta Fir.s {.Ih'us shastciisis). 



Above the forest of poiulerosa pines, and therefore not connected 

 witli siniihir forests elsewhere, a belt of Shasta lirs avera«4in<j;" 2 or 3 

 miles in breadth and 2,000 feet in vertical range completely encircles 

 the mountain. It is the distinctive forest of Shasta — a forest of tall 

 stately trees, dark, sonilxn', and free from underbrush, tlKagii here and 

 there beds of the low mountain man/anita {ArctosiKpliiiJos ncrddciisis) 

 afford a pleasing relief from the uniform darlc brown of the surface 

 carpet — usually a shallow hjyer of tir needles mixed with decayed cones 

 and wood. The massive trunks, which on the steep slopes are often 

 swollen just above the ground to give greater strength to resist the 

 l)ressure of snow, average from 4 to G feet in thickness and some attain 

 a diameter of 7 or 8 feet. Above the level of winter snow their northern 

 sides are usually covered with the handsome bushy yellow lichen, 

 Evernia nilpina, which also clothes many of the branches; and in the 

 denser parts of the forest the trees are draped with pendant masses of 

 the long black-beard lichen, Alectoria fremonti. The forest almost 

 everywhere consists of large mature trees, and is free from evidences of 

 fire; but in one ])lace, between Mud Creek Canyon and Cold Creek, a 

 considerable area, evidently an old burn, is covered with young trees 

 averaging perhaps 20 feet in height. 



As a rule, the Shasta firs stop abruptly where the white-bark pines 

 begin, and trees at their ui)per normal limit are of full size. But now 

 and then on the steep and relatively warm southwesterly slopes of 

 the ridges, dwarf Shasta firs occur. The highest point at which such 

 were observed was at an altitude of S,000 feet on the east rim of INlud 

 Creek Canyon, where a few stunted trees 3 or 4 feet in height were found 

 mixed with white-bark pines. On a similar warm slope west of Squaw 

 Creek a scattered line of these trees was noted at an altitude of S,100 

 to 8,.")00 feet. Here the largest were 20 feet in height. Their bark dif- 

 fered materially from that of trees lower down, being pale grayish 

 instead of dark brown, and thin, smooth, and full of blisters, instead of 

 thick and deeply furrowed. These lir trees were mistaken for another 

 si)ecies until 1 had the good fortuiu' to tind a few bearing cones, which, 

 on August J, were two-thirds or three-fourths grown. To my surprise, 

 they had long exserted bracts which, as in the young cones, stood 

 straight out horizontally. Very young cones (2 to 3.\ inches long) always 

 ap])ear to consist of bracts alone, the scales being hidden inside. On 

 breaking open the cones the tiny scales are seen encircling the axis; 

 they are less tlian half the size of the bracts and occu])y the inner half 

 of the diameter or section of the cone. 



The normal bark of tiie Shasta fir resembles that of the alpine hem- 

 lock. It is rather regularly furrowed vertically, and the plates between 

 the furrows are cracked horizontally, so that it sugg(!sts that of the 

 l)onderosa pine, though the ])lates are smaller and less red. Along the 

 lower edge of the Shasta lir belt the bark is darker and the cracks 

 and furrows are narrower. 



