SELLINGLUMBER 463 



low Pine. It is understood that these two terms are descrip- 

 tive of quality rather than of botanical species. 



(a) Dense Southern Yellow Pine shall show on either end 

 an average of at least six annual rings per inch and at least 

 one-third summer wood, or else the greater number of the rings 

 shall show at least one-third summer wood, all as measured 

 over the third, fourth and fifth inches of a radial line from the 

 pith. Wide-ringed material excluded by this rule will be ac- 

 ceptable, provided that the amount of summer wood as above 

 measured shall be at least one-half. 



The contrast in color between summer wood and spring 

 wood shall be sharp and the summer wood shall be dark in 

 color, except in pieces having considerably above the minimum 

 requirement for summer wood. 



In cases where timbers do not contain the pith, and it is 

 impossible to locate it with any degree of accuracy, the same 

 inspection shall be made over 3 inches on an approximate ra- 

 dial line beginning at the edge nearest the pith in timbers over 

 3 inches in thickness and on the second inch (on the piece) 

 nearest to the pith in timbers 3 inches or less in thickness. 



In dimension material containing the pith but not a 5-inch 

 radial line, which is less than 2x8 inches in section or less than 

 8 inches in width, that does not show over t6 square inches 

 on the cross-section, the inspection shall apply to the second 

 inch from the pith. In larger material that does not show a 

 5-inch radial line the inspection shall apply to the three inches 

 farthest from the pith. 



The radial line chosen shall be representative. In case of 

 disagreement between purchaser and seller the average sum- 

 mer wood and number of rings shall be the average of the two 

 radial lines chosen. 



(b) Sound Southern Yellow Pine shall include pieces of 

 Southern pine without any ring or summer wood requirement. 



BRANDED TIMBERS 



Proper service to buyers and users of Yellow Pine timber 

 demand correct grading, and the branding or marking of each 

 stick of timber showing its grade. 



Variation in the individual character of different pieces of 

 timber is responsible for the difference in strength. Structur- 



