CYPRESS FAIMILY 



71 



1. Libocedrus decurrens Torr. 

 Incense Cedar. Fig. 147. 



Libocedrxts decurrens Torr. Smiths. Contr. 6: 7. 1854. 

 Thuya craigana Murr. Rep. Bot. Exped. Oreg 2. 1854. 

 Hey'deria decurrens K. Koch. Dendr. 2: 179. 1873. 



Forest tree, often SO m. high, with an irregularly lobed 

 trunk tape.ring from a broad base, sometimes 3-3.5 m. in 

 diameter, the upper branches erect, the lower curved down- 

 ward, branchlets flattened and often vertically placed, 10-15 

 cm. long, usually deciduous the second or third year; bark 

 10-25 mm. thick, bright cinnamon-brown, fibrous. Leaves 

 light green, closely adnate except at the tip, 3 mm. long or 

 on leading shoots 10 mm. long, the lateral pair glandless, 

 nearly covering the flattejied obscurely pitted inner pair ; 

 staminate flowers yellow, ovate, 6 mm. long; the ovulate yel- 

 low-green, with ovate acute scales ; cones pendulous, matur- 

 ing the first autumn, oblong, 20-25 mm. long; scales with 

 short, recurved mucro ; seeds oblong-lanceolate, 8-10 mm. long, 

 tlie narrow outer wing scarcely longer, the inner broader and 

 nearly equaling the scale. 



A characteristic tree of the Arid Transition Zone, extending from 

 the Santiani River, Oregon, southward through the Cascade Mountains, 

 Sierra Nevada, and Inner Coast Ranges to San Pedro Martir Mountain, 

 Lower California, ^^'ood light reddish brown, close-sjrained, light and 

 durable in contact with the soil, but often infected with dry rot. It is 

 of considerable commercial value for fencing, shingles, and lead pencils. 

 Tyi)e locality: upper waters of the Sacramento River. 



2. THUYA L. Sp. PI. 102. 1753. 



Aromatic evergreen forest trees with slender, erect or spreading branches forming a 

 pyramidal crown; branchlets pendulous, flattened, forming a flat horizontal frond-like spray; 

 buds naked; bark thin, scaly; wood close-grained, soft, with thin, white sapwood. Leaves 

 scale-like, decussate, the lateral pair compressed and prominently keeled, nearly concealing 

 the other pair. Flowers monoecious, terminal and. solitary; the staminate ovate, with 4-6 

 peltate scales, bearing 2-4 nearly globose pollen-sacs; the ovulate oblong, with 8-12 oblong 

 acute scales and 2 erect ovules to each scale. Cones maturing the first autumn, ovoid - 

 oblong, their scales thin and flexible, oblong, acute, and mucronate at the apex, the 2 or 

 3 middle pairs fertile. Seeds usually 2, erect, ovate, acute, compressed, light brown, with 

 broad lateral wings distinct at the apex; cotyledons 2. [Name ancient.] 



Four species, one in northwestern and one in northeastern America, the other two in China and Japan. 

 Type species. Thuya occidcntalis L. 



L Thuya plicata D. Don. 



Giant Cedar. 



Fig. 



148. 



Thuya tlicata D. Don. Hort. Cantab, ed. 6, 249. 1811. 

 Thuya gigantca Nutt. Journ. Phila. Acad. 7: 52. 1854. 

 Thuya mensiesii Carr. Trait. Conif. 106. 1855. 



A handsome tree, attaining a maximum height of 

 60-70 m. and a diameter of 5 m., the trunk tapering and 

 strongly buttressed at the base, the branchlets bright 

 green and shining on the upper surface, paler on the 

 lower, usually falling- the third year; bark 1-2 cm. thick, 

 bright cinnamon-brown, divided into broad, rounded 

 ridges, separating into fibrous shreds. Leaves ovate, 

 short-pointed, bright green and shining, 3 mm. long, 

 obscurely glandular-pitted, those on the leading shoots 

 twice as long, long-pointed, and conspicuously glandular; 

 staminate flowers brownish, about 2 mm. long; cones 

 clustered near the ends of the branches, strongly re- 

 flexed, 10-12 mm. long ; scales leathery, thickened at the 

 apex and ofteji with a short, stout bristle ; seeds 2, or 

 sometimes 3, to each of the central scales, about 6 mm. 

 long; wings divergent at the apex, usually a little longer 

 than the seed. 



Moist bottom lands or rarely on dry ridges from sea level to 

 6000 feet altitude. Humid Transition and Canadian Zones; Portage 

 Bay, Alaska, southward along the coast to Mendocino County, 

 California, and through the Cascade Mountains of Washington and 

 Oregon, and eastward to western Montana. Type locality: Nootka 

 Sound. 



