ROS ACE: SILVA OF NORTH AMERICA. 87 
through Washington and Oregon to the valley of the Pitt River in California, and ranges southward 
through Idaho and Montana to the valley of the Flat Head River at the western base of the Rocky 
Mountains. It is found in wet sandy soil in the neighborhood of streams, where it often forms impene- 
trable thickets of considerable extent, and is most abundant and attains its greatest size in the valleys of 
western Oregon and northern California. 
The wood of Crataegus Douglasii is heavy, hard, tough, and close-grained, with a satiny surface 
susceptible of receiving a beautiful polish ; it is rose-colored, with thick pale sapwood composed of thirty 
to forty layers of annual growth, and contains many thin medullary rays. The specific gravity of the 
absolutely dry wood is 0.6950, a cubic foot weighing 43.31 pounds. It is used for wedges, malls, and 
the handles of tools. The fruit, which is produced in great profusion, is a favorite article of food with 
the Indians. 
Tn the dry interior parts of the continent Crategus Douglasii is represented by the variety rivu- 
laris,' which, in its extreme form, is distinguished by narrowly lanceolate simply serrate membranaceous 
pale leaves; but in northern Montana, where the black-fruited Thorns abound, it passes into the form 
with larger thicker incisely cut leaves, the plants in one thicket often showing both the extreme and all 
the intermediate varieties of foliage ever produced by this tree. 
Crategus Douglasii, var. rivularis, is usually a low intricately branched armed or unarmed shrub. 
It is common in the coast region of Oregon, and is the usual form in the region bordering the shores of 
Puget Sound; it ranges southward to Sierra and Plumas Counties, California,” and extends over all the 
mountain ranges of eastern Oregon and Washington ; it abounds on those of Idaho, Montana, and 
Utah, and spreads through Colorado * to the Pinos Altos Mountains of New Mexico, and grows along 
the borders of streams and mountain meadows, generally at high elevations. 
Crategus Douglasii was discovered by David Douglas‘ in the valley of the lower Colorado River, 
and in 1826 or 1827 was introduced by him into the garden of the London Horticultural Society, where 
it flowered ten years later. 
In cultivation Crategus Douglasii is a rapidly growing round-headed tree, soon attaining in good 
soil a height of eighteen or twenty feet; it is hardy on the Atlantic coast as far north as Nova Scotia, 
and in eastern Massachusetts covers itself every year with its handsome flowers and abundant black 
fruit. 
1 Sargent, Garden and Forest, ii. 400. Mespilus rivularis, Wenzig, Linnea, xxxviii. 187 ; Bot. Centralbl. 
Crategus rivularis, Nuttall; Torrey & Gray, Fl. N. Am. i. xxxy. 342. 
464, — Dietrich, Syn. iii. 161. — Walpers, Rep. ii. 58. — Nuttall, 2 Greene, Fl. Francis. i. 53. 
Sylva, ii.9.— Regel, Act. Hort. Petrop. i. 107. — Watson, King’s 8 Coulter, Man. Rocky Mt. Bot. 88. 
Rep. v. 92.— Engelmann, Bot. Gazette, vii. 128. — Sargent, Forest 4 See ii. 94. 
Trees N. Am. 10th Census U.S. ix. 74. — Macoun, Cat. Can. Pl. 5 Garden and Forest, i. 201. 
i, 522. 
