CYPRESS A.ND JUNIPER TREES OF ROCKY MOUNTAIN REGION. 11 



OCCURRENCE AND IIABITg. 



In the Verde River Canyon grove smooth cypress grows abund- 

 antly in gravelly and shaly soils on benches, gentle slopes, and low 

 ridges at elevations between 3,700 and 5,500 feet. It is best devel- 

 oped in protected watered gulches and on the gentler slopes and 

 benches where the soil is moist. At low elevations it is associated 

 with Pinus monophylla, Pinus edulis, Quercus chrysolepsis, and Rhus 

 laurina, while higher up it forms nearly pure stands. 



Little is known at present regarding the light requirements of 

 smooth c}-press during its early stages of growth, but in later life, 

 judging from the greater density of its crown, this species should be 

 as tolerant of shade, if not more so, than Arizona cypress. 



Smooth cypress is a prolific seeder, usually producing cones every 

 year. The fresh seed shows a moderately high percentage of germi- 

 nation, while the vitality of older seed probably declines rapidly after 

 the fifth year. 



LONGEVITY. 



The extreme age attained by this species has not yet been deter- 

 mined, but it is probably as long lived as Arizona cypress. The 

 largest trees found so far are at least 200 or 250 years old. 



GENERIC CHARACTERISTICS OF JUNIPERS. 



The junipers are evergreen trees that in general appearance some- 

 what resemble the cypresses, though their berrylike fruits at once 

 distinguish them from the latter. The adult foliage of most junipers 

 covers the branchlets closely and consists of short minute scalelike 

 sharp-pointed leaves arranged in groups (whorls) of three or in oppo- 

 site pairs, each of the latter alternating in position around the stem. 

 In some species all of the adult leaves occur in threes instead of in 

 pairs and are then much longer, needlelike, standing out loosely at 

 regular intervals (Pis. VI, - VII) . The margins of the leaves are 

 smooth or minutely toothed. The juvenile or primary foliage pro- 

 duced by seedlings and older young plants of the first group of junipers 

 noted is more or less similar in general appearance to adult foliage of 

 the last group mentioned. This primary foliage gradually gives way, 

 however, as the plants grow older to the adult scalelike form of 

 leaves. The close scalelike type of leaves very often have a pit or 

 resinous gland on the back (PL XIII) . When bruised, the f oliage of 

 junipers emits a pungently aromatic odor. 



The needlelike seed-leaves of junipers are 2 to 6 in number 

 (PL XIX). 



