718 JOURNAL OF FORESTRY 



bility, traveling expenses to and from the chance, general conditions on 

 the area, and the weather conditions. 



On large chances in the white-pine region the costs vary from 4 cents 

 to 7 cents per acre, with an average of about 5 cents per acre. The 

 costs are made up about as follows : Field, 50 per cent ; office, 20 to 30 

 per cent; travel time and expenses, 20 to 30 per cent. The costs of 

 appraisals in the yellow-pine and the larch-fir types are not as high 

 as the costs given above. Small chances cost much more than large 

 chances because the same amount of travel time and expense is gener- 

 ally required per acre. Assuming an average stand of 15 thousand feet 

 board measure per acre, which is about representative for the entire 

 white-pine type where appraisals have been made, the cost per thou- 

 sand for making appraisals is three-tenths of a cent. 



THE METHOD OF LOGGING 



Probably one of the most important things which the appraiser must 

 do on all logging chances is to determine the most feasible and most 

 economical method of logging. The best way, in case of doubt of de- 

 termining which of two methods is the most feasible, is to figure the 

 costs in each case. 



ANALYSIS OF COSTS 



There is generally a large amount of detail considered in the field, 

 but all the factors, both primary and secondary, can be based on a com- 

 paratively few simple facts in the final analysis. The natural or pri- 

 mary factors are those which determine for dififerent parts of the oper- 

 ation the varying amounts of work which can be accomplished under 

 the given natural conditions of timber and topography. The artificial 

 or secondary factors are based upon the variables which deal with the 

 costs as affected by labor efficiency, and such factors which depend 

 upon the primary factors in each case directly. To take the operation 

 of swamping and skidding as an example, the primary factors are as 

 follows : 



(a) Swamping: 



Species ; per cent and clear length of each which determines 



the amount of brush to be trimmed. 

 Undergrowth ; kind, density, and size. 

 Windfall ; amount and size. 

 Surface ; rough or smooth. 

 Rock. 



