COULTER PINE 



By E. N. Munns 



Forest Examiner, U. S. Forest Service 



Coulter pine (Pinus coulteri) is a tree limited in its distribution en- 

 tirely to California. It is of no importance commercially at the present 

 time, but is of value as a soil cover in regions where tree growth is 

 almost absent, though from a cover standpoint it is not so important 

 as the chaparral species with which it is associated. It will be of great 

 value in the future for forest planting, as it has potentialities for semi- 

 arid regions of poor site conditions and for elevations below the range 

 of the commercial tree species. It has already been introduced success- 

 fully into foreign countries. For landscape work the tree is prized be- 

 cause of its habit of retaining a dense, heavy foliage close to the ground 

 when grown in the open. 



Coulter pine is not fastidious as to soil. Wherever the tree is able 

 to get a foothold, it will grow, whether on an exposed cliff with little 

 soil covering or in deep soil on level ground. It has been found grow- 

 ing in a loose granitic sand and in all the gradations from that up to 

 a stiff adobe, but apparently does best in a granitic loam. From the 

 locations in which the tree grows^ it is evident that it can get along 

 with less soil water than any other tree species of the region, with the 

 possible exception of knobcone pine. The presence of water does not 

 keep the tree out, however, for it grows in meadows where willows 

 alone hold forth, and in creek beds with red alder, sycamore, and Cot- 

 tonwood. In such sites, the tree makes as good a growth as it does on 

 the north slopes at 5,000 feet, where it probably attains its optimum 

 in southern California. Jepson reports the tree as growing in the Santa 

 Lucia Mountains in a canyon not far from redwoods, on a ridge at 

 2,200 feet with yellow pine, and on the driest and rockiest chaparral- 

 covered slopes with knobcone pine. 



Coulter pine is an inhabitant of dry mountain slopes and is found as 

 scattered trees or stands along the Coast Range from Mount Diablo to 

 the Mexican border. In its best development it forms rather open 

 stands at lower elevations than yellow or Jeffrey pines, though freely 



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