EVERGREENS OF COLORADO 43 



possesses the characteristic odor of the eastern red cedar. It is very 

 durable in contact with the soil. The foliage of the Rocky Mountain red 

 cedar is usually bluish green in color or silvered, a character which helps 

 to distinguish it from the one-seeded red cedar, which has yellowish green 

 foliage. The scale-like leaves are very small, short, and closely flattened 

 against the twig, while those upon the strong-growing shoots are slender 

 tipped, and often reach one-half inch in length. 



The fruit requires two seasons for ripening. Mature berries are 

 usually about one-fourth inch in diameter, bluish or black, covered with 

 a heavy bloom. The seeds are commonly one or two in number, and are 

 covered with a hard, bony shell with several ridges extending lengthwise. 



This tree has been so diligently sought out and cut for fence posts, 

 wherever it occurs, that it is now difficult to find specimens of large or 

 medium size. It is one of our most easily transplanted evergreens, when 

 handled in moderate size, and is well adapted to the formation of low 

 hedges in dry situations, as it stands shearing well. Like the other red 

 cedars, it is difficult to grow from seeds, which require careful cleaning 

 and stratifying. Germination requires two seasons, as a rule. 



TREE ZONES IN COLORADO. 



In passing from the Great Plains to the top of the Continental Divide 

 or to the summit of one of the peaks where snowbanks lie throughout the 

 year in Colorado, an observant person is impressed with the changes that 

 take place in the character of the vegetation at different altitudes. As the 

 climate changes at the different levels, so the plant life also varies, not 

 abruptly, to be sure, but yet in fairly well marked belts or zones. Upon 

 the plains before irrigation was practiced, there were no trees except 

 cottonwoods and willows along streams and draws or occasionally in de- 

 pressions that caught the surface run off of surrounding slopes. This 

 may be called the Plains Zone. 



At the lowest and outermost range of foothills one meets the van- 

 guard of the great forests of evergreen trees that lie higher up. This 

 second or foothill zone lies mainly between the altitudes of 6,000 and 

 8,000 feet. The most characteristic tree of this zone is the yellow or 

 rock pine, which forms open groves of dwarfed and round topped trees 

 upon the driest ridges and among the rock piles of the outer hills or grows 

 in closer stands of well developed specimens on the gentler and moister 

 slopes higher up. In some portions of the state this zone is quite 

 largely occupied by pinyon pine and red cedar with Douglas fir crowding 

 into gulches and sheltered depressions upon northern and eastern slopes. 



Above this zone lies the montaine zone with the lodgepole pine as 

 the characteristic tree. This species often forms a dense, unbroken forest 

 cover, on northern and eastern slopes, mixed at the lower borders with 

 rock pine, especially on southern and western exposures. The Silver 

 Spruces appear in limited numbers along the streams, and in Southern 

 Colorado the Douglas fir and white fir also occupy a prominent place in 

 this zone. 



The fourth zone, known as the sub-alpine zone, extends approximately 

 between the altitudes of 10,000 and timberline or the level at which tree 



