CUPRESSUS 233 



summer tracheicls small, rarely large, not numerous. Resin cells not 

 numerous, 20-25 /* wide, 150-200 /j. long, chiefly about 175 /u,. 

 Tangential. Rays medium, wholly i-seriate ; the cells broadly oblong or 

 oval, sometimes round, the walls thick. 



A light, hard, and strong wood which is very durable in the soil. 



Relative specific gravity 0.4621 



Approximate relative fuel value 46.16 



Coefficient of elasticity in kilograms on millimeters . . 1217. 



Ultimate transverse strength in kilograms 379. 



Ultimate resistance to longitudinal crushing in kilograms 7435. 



Resistance to indentation to 1.27 mm. in kilograms . . 1317. 

 (Sargent) 



Oregon, not more than thirty miles from the coast ; valley of the upper 

 Sacramento River, California (Sargent). 



3. C. pisifera, Sieb. et Zucc. 

 Jap. = Saivara 



Transverse, Growth rings narrow, uniform ; the usually dense and very 

 narrow summer wood of 3-5 tracheids, the transition to the spring 

 wood somewhat abrupt ; the spring wood open, the large, squarish- 

 hexagonal tracheids in very regular rows, uniform, rather thin-walled. 

 Resin cells few, dark, and prominent, zonate in the summer wood. 

 Medullary rays not prominent, I cell wide, narrow, distant 2-17 

 tracheids. 



Radial. Rays devoid of tracheids, nonresinous, the cells contracted at 

 the ends, equal to 5-6 spring tracheids : the upper and lower walls 

 thin, rather unequal, not obviously pitted ; the terminal walls thin, 

 chiefly curved, not pitted or locally thickened ; the lateral walls with 

 oval, bordered pits, chiefly 2 per tracheid in radial series, or in the 

 marginal cells and low rays smaller and upwards of 6 per tracheid. 

 Bordered pits elliptical, large, rather numerous in i row or sometimes 

 in pairs. Pits on the tangential walls of the summer tracheids rather 

 few, small, flat, and inconspicuous. Resin cells few in the summer 

 wood, 12.5-20 /A wide, 170-250 ju, long. 



Tangential. Rays low to medium, narrow, nonresinous ; the cells rather 

 variable from oblong to oval or round, chiefly rather oblong, rarely 

 if ever in pairs. 



4. C. nootkatensis, Lam. 



Yellow Cypress. Sitka Cypress 



Transverse. Growth rings unequal. Summer wood very thin, of 2-6 

 tracheids, the transition to the spring wood gradual. Spring tracheids 

 chiefly large, but very variable and often in irregular rows, squarish 

 Resin cells prominent and rather numerous, either scattering or com- 

 pressed into narrow bands in both the spring and summer wood. 

 Medullary rays resinous, prominent, i cell wide, distant about 2-17 

 tracheids. 



