460 APPENDIX A 



all logs of this class, not barred by knots or defects. This diameter will vary with 

 the same species in different regions, and for different species. 



Effect of Defect upon Grades of Logs. The defect most easily seen, both in logs 

 and standing timber, is a knot. In grading hardwood logs, one sound, bright knot, 

 with a maximum diameter of 4 inches is taken as a standard defect. Other defects 

 are compared with this knot, on the basis of an equal amount of damage to quality. 

 These may be worm holes, smaller or larger knots, shake, rot, cat faces or fire scars. 

 The maximum number of standard defects, or their equivalent, is prescribed for each 

 grade of logs. 



For conifers, a different system is employed, and the specifications lay stress on 

 the possible percentage of yield of certain grades, with indication as to the general 

 appearance and character of defect in logs which will yield this ratio. 



Defects are of two classes, those which cause loss of grade, but no discount in 

 total scale, i.e., sound defects, and those which require elimination from the scale 

 of the defective part. To the first class belong sound knots, stain, firm red heart 

 and pitch. In the second class fall rot, shake, fire scars, cat faces, and crook or 

 sweep. Worm holes may be in either class, according to size and frequency. 



In the grading of hardwood logs, no distinction is made, and the presence of more 

 than two " standard " defects serves to throw the log into the lowest class, or No. 

 2, except when over 24 inches in diameter, when it must cut at least 75 per cent of 

 No. 1 common and better lumber. 



With conifers, the presence of either class of defect will not reduce the grade of 

 a log as long as the minimum percentage of upper grades can still be secured. But 

 in reality, the value of the log is greatly lessened by such defects. With increasing 

 amounts of defect, the log is de-graded either to second or third grade, and finally 

 is rejected as cull. 



360. Examples of Log Grades. Hardwoods — National Hardwood Lumber 

 Association, 1916 Oak, White and Red. 



No. 1 logs. 2 inches of bright sap is no defect. Sap in excess of 2 inches is one 

 standard defect. 



No. 1 logs must be 24 inches and over in diameter. 



24 to 29 inches inclusive will admit of one standard defect or its equivalent. 



30 inch and over will admit of two standard defects or their equivalent. 



Select. Select logs must be 18 inches and over in diameter. 



2 inches of bright sap is no defect. Sap in excess of 2 inches is one standard defect. 



18 to 21 inches wide inclusive must have ends and surface clear. 



22 and 23 inches will admit of one standard defect or its equivalent. 



24 inches and over will admit of one more standard defect than is admitted in No. 

 1 logs of same size. 



No. 2 logs. No. 2 logs must be 10 inches and over in diameter. 



Bright sap is not a defect in this grade. 



16- and 17-inch will admit of one standard defect or its equivalent. 



18 to 23 inches inclusive will admit of two standard defects or their equivalent. 



24 inches and over must cut 75 per cent or more into No. 1 common and better 

 lumber. 



The grades for other species arc similar. 



Softwoods — Columbia River Log Scaling and Grading Bureau, Washington 

 and Oregon, 1920. 



No. 1 Logs. No. 1 logs shall bo logs which, in the judgment of the scaler, will be 

 suitable for the manufacture of lumber in the grades of No. 2 clear or better to an 

 amount of not less than 50 per cent of the scaled contents. 



