DEVELOPMENT OF MICHIGAN WASTE LANDS 435 



the clutch and drum principle. Selling at a price 

 ranging from $100 to $400, these pullers are sold to 

 a reported amount of about $1,000,000 annually. 

 Three-fourths of this business is domestic and direct 

 from factory to customer. About 10,000 machines 

 are produced annually, the company reports; and 

 the hand-power clutch and drum type predominate. 

 These hand-power machines are chiefly used on small 

 acreages. Experience has shown that usually the 

 best combination is of explosives and stump-pullers, 

 whereby the stumps are first riven to pieces and then 

 removed by the puller. 



In addition to explosives obtained through com- 

 mercial channels, the farmers of the cut-over area 

 have obtained large quantities of ^'TNT" relin- 

 quished by the United States Department of Agri- 

 culture to the State Highway Department, and by 

 the Highway Departments to the local farm bureaus 

 for land-clearing operations. The reported contri- 

 butions thus furnished 750,000 pounds. The price 

 was very much less than that normally paid for ex- 

 plosives, since, as salvaged war material, it was not 

 distributed on a commercial basis. It proved a great 

 boon to the stump country, but aroused some oppo- 

 sition on the part of private concerns handling ex- 

 plosives, and for this or other reasons, this source of 

 supply was largely cut off in the spring of 1921. 

 There remained large quantities of "government" 

 picric acid, which it was planned to dispose of simi- 

 larly when a safe method of handling had been se- 

 cured. It is evident that land-clearing operations in 



