PINUS 325 



Staten Island, New York, thence southward to. western Florida and 

 through the Gulf States to Tennessee and eastern Texas ; through 

 Arkansas to Oklahoma ; southeastern Kansas, southern Missouri, and 

 in Union County, Illinois (Sargent). 



21. P. resinosa, Ait. 

 Red Pine. Norway Pine 



Transverse. Growth rings very thick, often double. Summer wood about 

 one fifth the spring wood, from which the transition is very gradual ; 

 not very dense, but when double the outer band is generally more open 

 with the tracheids less compressed, the inner band is more dense with the 

 tracheids usually thick-walled and more conspicuously compressed ; 

 the tracheids round-hexagonal, conspicuously unequal in regular rows, 

 the walls rather thick. Spring tracheids hexagonal, uniform in regular 

 rows, the walls thickish. Resin passages very scattering, not numer- 

 ous, large ; the epithelium not extensive, about 2 layers thick, the cells 

 of the layer next the canal radially flattened, those of the other layers 

 oval, often resinous. Medullary rays rather prominent and broad, 

 numerous, distant 2-9 rows of tracheids. 



Radial. Rays nonresinous, the ray tracheids low, marginal, rarely inter- 

 spersed, conspicuously dentate. Ray cells long and low, straight, or 

 in the summer wood often conspicuously contracted at the ends ; the 

 terminal walls thin and entire ; the upper and lower walls rather thin, 

 remotely and imperfectly pitted ; the lateral walls with very large, 

 oval or oblong, very variable pits, which become lenticular toward the 

 summer wood, 1-2, chiefly i, per tracheid throughout. Bordered pits 

 in i row, sometimes in pairs, elliptical. Pits on the tangential walls of 

 the summer wood wholly wanting. 



Tangential. Fusiform rays not numerous, chiefly rather low and broad, the 

 'cells rather large and thin-walled throughout. Ordinary rays medium, 

 nonresinous, numerous, rarely contracted by much smaller and nar- 

 rower, interspersed tracheids ; the cells chiefly equal but not very 

 uniform, oval or squarish, rather large, and thin-walled, the lateral 

 walls very thin and chiefly concave. 



A tree 24-46 m. high, with a trunk upwards of 1.37 m. in diameter. 

 Wood light, not strong, hard, rather coarse grained, and compact. 



Specific gravity 04854 



Percentage of ash residue o- 2 7 



Approximate relative fuel value . . . 48. 4 ! 



Coefficient of elasticity in kilograms on millimeters . . . 1132. 



Ultimate transverse strength in kilograms 341. 



Ultimate resistance to longitudinal crushing in kilograms . 7274. 



Resistance to indentationlo 1.27 mm. in kilograms . . . 1353. 

 (Sargent) 



