10 BULLETIN 91, U. S. DEPARTMENT OF AGRICULTURE. 



is required with this type. The vertical-lift machines are more pow- 

 erful and seem to require less repairs than the average capstan 

 machine. On the other hand, the machine must be moved for each 

 stump, requiring four or five horses. Holes must be dug under the 

 roots of each stump. 



POWER MACHINES.' 



Power machines have been used to a limited degree throughout 

 this region. On large tracts of land, with a good outfit and an effi- 

 cient crew, the clearing probably can be done with a power machine 

 as cheaply as and considerably faster than by any other method in 

 use at the present time. 



COST OF CLEARING LAND. 



The cost of clearing land in the Lake States varies greatly. It 

 runs from $5 to about $100 per acre. The cut-over jack-pine land 

 is the cheapest to clear and green hardwood and unburned swamp 

 land the most expensive. The cost of clearing depends on the fol- 

 lowing factors : 



(1) The quantity of second growth and logs per acre: The cost of disposing of these 

 runs from $5 to $25 per acre, and even higher, with an average of about $10. 



(2) The kind of stumps and the number of years since logging: All green hardwood 

 stumps are very expensive to remove. Green birch and basswood are perhaps the 

 most difficult. Most hardwoods decay so that they can easily be removed within 10 

 years from the time of logging, provided the sprout growth is not allowed to develop. 

 Jack pine and hemlock will decay at about the same rate as hardwood. Scrub oak is 

 more resistant to decay than the other hardwoods. White pine and Norway pine will 

 not decay in 50 years. The cost of removing pine stumps from 5 years to 25 years after 

 logging is practically the same. 



(3) The size and number of stumps per acre: The number of white-pine stumps per 

 acre varies from 10 to 100, with an average of about 45. Some hardwood lands have 

 more than 400 stumps per acre. Some contractors taking work by the job count the 

 stumps and then add 10 per cent to the number to cover those that were overlooked or 

 burned close to the ground. It usually is more expensive to remove severely burned 

 white-pine stumps than it is to remove a sound stump. For this reason any system of 

 burning that will not burn the roots below plow depth does not reduce the cost of stump- 

 ing. A pretty close approximation of the average number of stumps per acre may be 

 obtained by counting the number of stumps on several sample acres. A circle of 117.8 

 feet radius contains an area of 1 acre. A rapid and convenient method is to stand 

 on a stump and count all the stumps within 118 feet of it. 



(4) Soil and topography: Where stump-pulling machines are used, the cost of stump- 

 ing in sandy soils is less than in heavier soils. Where dynamite is used, the cost in 

 heavier soils is less than in sandy soils. On many tracts the land was swampy at the 

 time of the tree growth, and the rooting system was consequently shallow. After the 

 tract shown in figure 8 was logged, fires burned off all the litter and most of the humus, 

 leaving nearly all of the roots exposed. On many such areas a heavy team will tip 

 out most of the stumps by a direct pull. For this reason this type of clearing is not 

 usually expensive. (See "Tract No. 20," p. 22.) It is more expensive to pull stumps 

 on steep land than it is on level land. It is more expensive to stump stony land than 

 land free from stones, because the cleaning of the stumps is more difficult. 



i See Thompson, Harry, Cost and methods of clearing land in western Washington, U. S. department 

 of Agriculture, Bureau of Plant Industry. Bulletin 239, 60 p., 25 fig., 1912, for use of power machines for 

 land clearing. 



