326 JOURNAL OF FORESTRY 



probable that there are regions in which a universal volume table 

 can be applied and mechanical methods used in volumetric survey, 

 but such does not seem to be the case in this region at present. But 

 given fair volume tables, such as a skilled volume cruiser can him- 

 self have prepared within a few days, the accuracy of volume results 

 depends far more upon the capacity of the appraiser and cruiser than 

 upon the method which is employed. Using the strip method as the 

 basis of volumetric survey, it is safe to say that it requires two years 

 for an untrained man, forest school graduate or otherwise, to qualify 

 as an accurate cruiser, and even in this time unless he is adapted to 

 the work and gives conscientious application his results show only 

 a fair degree of accuracy. 



In the more or less mechanical process of tallying the trees on 

 the strips there are two sources of error which must be guarded 



obtained by means of so-called tree volume tables which give the contents in board 

 feet or log scale of trees of different diameters containing different numbers of logs 

 and utilized to specified diameters at the small end of the top log. These volume 

 tables are based on measurements of trees felled in logging operations employing 

 different degrees of utilization. In connection with this cruise or survey, in order 

 to facilitate determining the value of the soil for growing timber, the areas of the 

 different forest "types" (classes of stands in which the trees will yield one, two or 

 three 16-foot-long saw logs) are mapped. 



Experience has shown that the most efficient crew for strip volume survey in 

 appraisals of timber for eastern National Forests consists of two men. The forward 

 man in the crew, a compassman who keeps the chain-wide strips straight and parallel, 

 acts as tallyman for recording the timber data, changing the tally sheet whenever 

 the forest "type" changes and hereafter changing it by small logging units as well. 

 A surveyor's chain or tape for measuring the distances traversed on the strips and 

 for obtaining the relative location of the topographic features on the strips as they 

 are crossed is attached to his belt and drags behind him. His work is largely mechani- 

 cal, but it requires from four to six months training for a man to become a compass- 

 man and tallyman. The rear man of this crew is the timber cruiser and is responsible 

 for the timber volume. He attends to the rear end of the chain, calls the distances 

 or "chaining," levels the chain to obtain accurate horizontal measurements of the 

 distances where the surface is broken, and makes the cruise or measurements of the 

 timber. He directs the compassman to record the kind of tree, its diameter, number 

 of merchantable logs, and gives in addition for each tree such minor products as 

 ties, poles, posts, and the data for determining the amount of pulpwood, tannin, 

 extract stock, tanbark, and such other products as are merchantable. He indicates 

 in his notebook the changes in forest "types" or stand classes, records the data for 

 the skeleton map of the tract and in case a topographic map is to be made, he also 

 records data for this, keeping track of the chainings as well as the compassman. In 

 the examination of large tracts, several such crews are under a "chief of party" 

 who has general responsibility for the work and usually prepares the report. A 

 form submitted by him with his report, gives his associates and the different classes 

 of work performed by each, and in connection with the tally sheets and their relation 

 to the base line or periphery of the tract, permits the placing of the responsibility 

 for the accuracy of the work on any portion of the tract. For a full discussion of 

 the distinctive details of Appalachian timber cruising, see paper by R. C. Hall on 

 "Timber Estimating in the Southern Appalachians" on p> 310 of this issue of the 

 Journal of Forestry. 



