FOREST TREES OF THE PACIFIC SLOPE. 325 



in length, with a minute point at the top. A dry, sweet, very thin, yellowish 

 pulp covers the hard, thick-shelled seed. The fruit of this tree is extensively 

 eaten by birds, which thus assist greatly in disseminating the seeds, which 

 are not injured by digestive action, but on the contrary arc probably better pre- 

 pared for germination. Flood waters also aid in distributing the seed. Exten- 

 sion of the species by direct seeding from the tree is slow. Wood, rather heavy, 

 moderately soft, brittle, and very wide-grained; the whitish sapwood is exceed- 

 ingly thick and the heartwood is a bright yellowish-white. Of no economic use, 

 owing to rarity of occurrence and poor timber form in the far West. In the 

 East it produces good but not extensive quantities of excellent saw timber, which 

 is made into second-class lumber. 



Longevity. — The age attained by the Pacific form is unknown. It grows 

 rapidly in the East, attaining great age, but appearing to reach maturity in 

 about 75 or SO years. Eastern forest-grown trees from IS to 24 inches in 

 diameter are from 140 to 1G5 years old. 



RANGE. 



From St. Lawrence River (St. Helens Island, near Montreal) to southern Ontario; in 

 the United States from Massachusetts (Massachusetts Bay) to northwestern Nebraska, 

 North Dakota, southern Idaho (Boise), eastern Washington and Oregon (Snake River), 

 western Washington (Puget Sound), Nevada (East Humboldt Mountains), New Mexico, 

 and south to Florida (Biscayne Bay and Cape Romano), middle Tennessee, Missouri, 

 eastern Kansas, Indian Territory, and eastern Texas. 



OCCURRENCE. 



Rocky bluffs and slopes near streams ; in dry broken rock, or poor gravelly soil. Lack 

 of moisture (not a requirement) produces stunted, scraggy trees. Cultivated in moist, 

 rich soil, it is more like the typical eastern form. Scattered singly or in small groups ; 

 not common. 



Climatic Conditions. — Similar to those of western yellow pine. 



Tolerance. — Endures considerable shade throughout life. 



Reproduction. — Fairly abundant seeder, but reproduction scanty. 



Palo Blanco. 

 Celti* reticulata Torrey. 



DISTINGUISHING CHARACTERISTICS. 



The palo bianco, known almost entirely by this Spanish name, is considered 

 by some authors to be only a variety of the eastern smooth and shiny-leafed 

 Celtis mississippiensis Bosc. As palo bianco occurs in the southwest and in 

 the Colorado Desert part of California, it is a very different tree in habit from 

 its eastern relative, particularly in its shorter, wider, ami rough leaves (fig. 

 152). 



It ranges in size from a low, densely branched shrub to a ronnd-crowned, 

 short-trunked tree from 15 to 30 feet high and from G to 10 inches or more 

 in diameter; the bark is bluish, ashy gray, and is rough, with prominent, thin, 

 short, projecting ridges. Mature leaves (fig. 152), thick and leathery, are very 



veiny, dee]) green mi their upper sides; very rough (like sand-paper) — s e- 



tinies only slightly rough, however, and very light yellowish green beneath, 

 with or without minute straight hairs, and with a conspicuous network of small 

 veins; margins of the leaves mainly without teeth. Mature fruit (tig. 152), 

 ripe in autumn, orange red. Wood, somewhat lighter than that of Celtia mis- 

 8i8sippiensi8 and of about the same weight as that of C. occidentalism is not 



" See characterization of wood under genus, which holds good for this species. 



