62 BULLETIN" 711, U. S. DEPAETMENT OF AGKICULTUEE. 



tion to the distance, however, as a large part of the time is consumed 

 in hooking, starting, imhooking, and the like, which is the same 

 whatever the distance. 



The economic range, of course, varies with the style of yarding. 

 The high lead affords its peculiar advantages only when confined 

 to a distance of from 500 to 700 feet; ground yarding is generally 

 worked on a maximum of from 600 to 900 feet; while the overhead 

 systems are worked to best advantage on longer reaches, say from 

 900 to 1,500 feet. Of course, it is sometimes necessary and advisable 

 to use these sj'^stems, particularly the latter, at greater distances. 



The less of the total burden of transportation assigned to the rail- 

 road, the more comes on the yarding, increasing the distance and 

 lowering the output. So the topography of the country has a great 

 deal to do with fixing the yarding distance. While it is possible to 

 build railroads nearly everywhere, it is not always practical to do so 

 because of the high cost of grading and maintaining the track, the 

 large investment, and the danger and high cost of operating trains 

 on heavy grades. The volume of the stand affects the yarding dis- 

 tance in much the same way, as more miles of spur railroad can 

 economically be built where the stand is heavy than where it is light. 



(5) Size of crew. — Up to a certain point the output increases as 

 the size of the crew is increased. On the other hand, a relatively 

 large output due to a large crew is not necessarily the most economi- 

 cal. Too much can be made of this factor, since, with any system of 

 yarding, the bulk of the crew is largely fixed. For example, in the 

 case of ground yarding, the crew, as a rule, consists of 11 men. 

 This type of crew is more or less elastic in its makeup, however, as 

 ground yarding crews consisting of as many as 14 are used ; others 

 contain as few as nine men. 



(6) Condition and care of equipment. — The output varies with the 

 condition of the equipment, the way it is used, and the length of life 

 expected of it. It is larger when up-to-date machines of the proper 

 size rather than old machines of the wrong size are used, when 

 jnachines are driven at practically their maximum speed instead of 

 slowly for the purpose of prolonging their life and reducing the cost 

 of maintaining them, and when lines, rigging, etc., are replaced as 

 soon as the signs of wear indicate that they may break, instead of 

 waiting for them to break a number of times before being replaced. 

 There must, of course, be a nice balance between the output and the 

 labor, equipment — maintenance and depreciation — and supply costs 

 per thousand feet. Most operators, no doubt, get as close to this 

 balance as is possible. There are some, however, who could reduce 

 the total cost per thousand feet for yarding by taking better care of 

 the equipment ; others who could reduce the cost by speeding up the 



