RESEARCH IN FOREST PRODUCTS 279 



In dimension material containing the pith but not a 5-in. radial line, which is 

 less than 2 by 8 in. in section or less than 8 in. in width, that does not show 

 over 16 sq. in. on the cross-section, the inspection shall apply to the second 

 inch from the pith. In larger material that does not show a 5-in. 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 be- 

 tween purchaser and seller the average summerwood and number of rings shall 

 be the average of the two radial lines chosen. 



(fc) Sound Southern yellow pine shall include pieces of Southern pine with- 

 out any ring or summerwood requirement. 



Within the past six months the West Coast Lumbermen's Associa- 

 tion adopted a density provision for Douglas fir which is the same in 

 principle, although there are some differences as to where measure- 

 ments are to be made and as to the minimum size of timbers in which 

 pith or "boxed heart" is permissible. 



The foregoing rules are of direct concern to lumbermen and for- 

 esters, particularly the latter, in a number of different ways. More and 

 more they are bound to exert a strong influence towards stability and 

 permanency of market prices of structural timbers because they will 

 assure clear cut grades and quality and will thus clarify competition 

 and establish sound lumber values. The forester whose responsibility 

 it is to appraise forests which contain structural timber will readily 

 appreciate the vital relation between these values and market move- 

 ments to his own work in the woods. Stumpage appraisals as con- 

 ducted by the Forest Service, for example, hinge sharply upon the 

 relative accuracy of the appraiser's estimate or calculation of the 

 quality of the standing timber and its manufactured market value. 

 Unless this be determined quite closely, a safe estimate of stumpage 

 values of the stand cannot be arrived at. It is obvious, furthermore, 

 that the success of forest administration and forestry itself is de- 

 pendent upon sound, clearly defined and stable market values and 

 that all factors which affect or determine the quality of the timber in 

 the standing tree and which can be isolated for practical use, aid 

 directly in the establishment of those values. 



But without further information which must be obtained through 

 studies in the forest the present forester cannot make full application 

 of the density principle. In a standing forest density is a variable 

 factor. One tree may contain timber of very high specific gravity, 

 while an adjacent tree may show the opposite. No studies have been 

 made to determine authoritatively the causes for these differences in 



