'396 FOREST TREES OF THE PACIFIC SLOPE. 



Oregon. — Whole wooded portion of State except Goose Lake region. Noted along 

 Columbia River in Sherman County, Blue Mountains, Mount Hood, Crater Lake on inner 

 slope of crater. 



California. — Northern part of State, Sierra Nevada, probably only on west slopes, 

 and ranges east of southern Sierra Nevada at high elevations. Noted at 3,000 feet at 

 south end Shasta Valley, on Mount Shasta up to 5,600 or 6,000 feet, especially in Mud 

 Creek Canyon and Squaw Creek, near Sissons and in McCloud Valley : in Trinity County, 

 on lakes at head of Canyon Creek ; Lassen Teak, Plumas, and Tahoe National Forests ; 

 Stanislaus National Forest at 5,000 to 7,500 feet, Yosemite Valley, Bubbs Creek (tribu- 

 tary South Fork Kings River), East Fork Kaweah Rher at 8,000 to 9,000 feet, east of 

 southern Sierras in Grapevine Mountains in Wood Canyon, in Panamint Mountains, 

 in Death Valley Canyon at 6,000 to 7,000 feet, or higher. Also reported in San Jacinto 

 Mountains, in canyon on east side below Round Valley at 7,500 to 8,000 feet. 



OCCURRENCE. 



Rocky cliffs and canyon sides, gulches, borders of high mountain streams, and 

 meadows, usually where soil is thin, gravelly, and often poor. Scattered singly and in 

 small clumps with broadleaf maple, mountain alder, birch (Alaska i, aspen, and western 

 serviceberry. Occasional large trees in southeastern Alaska, Vancouver Island, and Blue 

 Mountains of Washington. 



Climatic Conditions. — Similar to those of aspen. 



Tolerance and Reproduction. — Undetermined. Appears little tolerant of shade; seeds 

 rather sparingly. 



California Boxelder. 



Acer negundo calif ornicum (Torr. and Gr.) Sargent. 



DISTINGUISHING CHARACTERISTICS. 



California boxelder is usually called simply " boxelder," but it should be 

 distinguisbed from tbe eastern boxelder (Acer negundo L.), of which tbe 

 Pacific tree is a variety. 



A sbort and stocky tree from 20 to 50 feet bigb and from 10 to 30 inches in 

 diameter; sometimes taller and thicker. The clear trunk is short, the crown 

 broad, dense, and round-topped, and the bark of the trunk pale grayish brown, 

 with regularly deep furrows and narrow ridges. Mature twigs of the season 

 thickly coated with down, as are the mature 3-parted leaves (fig. 188) on their 

 under sides and sometimes on both surfaces. (Foliage and twigs of the 

 eastern tree are smooth or only slightly hairy.) Mature "seeds" or fruit (fig. 

 188) are also downy. The greenish flowers of boxelder differ from those of 

 Simple-leafed maples in being strictly male and female, and those of each sex 

 are borne on separate trees ; therefore only the female trees produce seed. 

 Male flowers occur in clusters of drooping, unbranched thread-like stems, 

 while the female flowers are on a drooping branched stem, both from buds on 

 twigs formed the previous year. The seeds, ripe in autumn, usually remain on 

 the twigs until or during the winter, their dead stems adhering to the branchlets 

 in spring. Wood, very pale lemon yellow or creamy white, the sap and heart- 

 w 1 scarcely distinct from each other. Variable from fine-grained to moder- 

 ately coarse-grained, light, soft, firm, but brittle. Suitable for second-rate finish- 

 ing, box-boards, and paper pulp, but the poor timber from and scattered supply 

 of the trees render the wood of little commercial importance. 



Longevity. — Not fully determined. One tree 12 inches in diameter showed 

 an age of 36 years. Gives evidence of being short-lived. 



Southern California (valley lower Sacramento River; valleys and coast ranges from 

 Sonoma County to Santa Barbara County, and western slopes San Bernardino Mountains*. 



