FOREST TREES OF THE PACIFIC SLOPE. 327 



OCCURRENCE. 



Low mountain canyons, dry or intermittent water courses, desert gulches, and borders 

 of rocky streams ; in dry, gravelly soil. Scattered singly and in small groups or 

 groves. 



CLIMATIC Condition's. — Similar to those of white alder. 



Tolerance. — Undetermined, but trees show marked tolerance of shade. 



Reproduction. — Abundant seeder. Germination, except in constantly moist soil, 

 tardy ; seedlings rather sparse. 



Family LAURACEiE. 



A small family (as represented in our forests) of trees characterized by the 

 pungent, aromatic taste and odor of their bruised green bark and foliage. It 

 includes the widely known camphor and bay trees of the Old World, our well- 

 known eastern sassafras tree, and a group of " loblolly " bay trees of our south- 

 ern forests, together with a single genus in the Pacific region. The foliage of 

 some of these species is evergreen, whereas that of others is shed each autumn. 

 The leaves of some are borne singly, those of others in pairs — one leaf opposite 

 another. In some species the flowers combine both male and female organs, 

 while in others male and female flowers are each borne on different trees. 

 Fruits of our representatives are berry or plum like, with one hard-shelled seed. 

 The wood of these trees, often hard and beautifully marked, is mainly of only 

 minor commercial importance. Economically, the camphor trees are the most 

 valuable of the group, all parts of the trees yielding camphor. 



UMBELLULARIA. LAUREL. 



Since this genus is represented by a single species only, inhabiting the Pacific 

 forests, its characteristics are given under that species. 



California Laurel; Oregon Myrtle. 



Umbelliilaria califoniica (Hook, and Arn.) Nuttall. 



DISTINGUISHING CHARACTERISTICS. 



California laurel is an evergreen tree, distinguished at once from all others 

 of its range by the strong camphoric-pungent odor <* of its crushed leaves or 

 green bark. Under the most favorable growth conditions, from 60 to 80 feet higb 

 and from 2i to 3i feet in diameter : exceptionally large trees are sometimes 4 

 feet through. In the dense forest it has a clean, straight trunk from 30 to 40 

 feet long and a narrow crown of close, small, upright branches. Elsewhere, 

 however, and much more commonly, it has a very short, thick trunk, surmounted 

 by large, long limbs which trend upward and form an exceedingly wide, dense, 

 rounded crown. In moist shaded mountain canyons and gulches it appears 

 in a many-stemmed shrubby form in clumps and thickets from 10 to 15 feet 

 high. Bark of large trunks is thin, very dark reddish-brown, and scaly ; the 

 stems of young trees are smooth, and dull grayish-brown. New leaves are 

 produced throughout the summer on the stems, which grow constantly in height. 

 This results in the branches being heavily foliaged. As a rule, the leaves of 



° The green bark and, particularly, the leaves possess a light volatile oil, follicles 

 of which are given off when either is crushed, and which when inhaled through the 

 nostrils produces severe pain over the eyes, at tended often by violent sneezing. Con- 

 tinued inhalation of the odor of fresh leaves usually produces slight dizziness, but appar- 

 ently no other alarming effects. The dried leaves produce the same effect, but less 

 violently. 



