14 BULLETIN 4%, U. S. DEPARTMENT OF AGRICULTURE. 



SUMMARY. 



(1) When the brush is lopped and scattered it rots more rapidly 

 than when either piled or pulled. This is due to the fact that two 

 types of fungi rot the brush, one entering the limbs and branches 

 not in direct contact with the ground and the other entering those 

 portions of the brush in actual contact with the soil. 



(2) The maximum gain in the rapidity of the rotting of the brush 

 when scattered over the same brush when left un lopped in the tree 

 tops is about one year. On dry areas, such as steep hillsides with 

 southern and western exposures, there is practically no difference in 

 the rate of rotting of the brush when scattered and when the tree 

 tops are left unlopped. 



(3) Brush when lopped and piled will apparently take from three 

 to six years longer to rot than when scattered or when left unlopped. 



(4) Brush when piled is rotted at the top by one group of fungi 

 and at the bottom by another group, while the middle of the pile, not 

 in contact with the soil and yet protected from the sunlight, ap- 

 parently will not rot to any extent until the pile disintegrates suffi- 

 ciently to expose these central layers to the soil moisture on the one 

 hand or to the sunlight on the other. 



(5) The same general facts as to the rotting of the slash hold for 

 all species of timber (pine, oak, etc.) examined in Arkansas. 



(6) Four fungi are the main agents in the rotting of oak slash in 

 Arkansas, viz, Stereum ramedle, S. umbrinum, S. rersiforme, and 

 S. fasciatum. 



(7) Two main fungi rot the shortleaf-pine slash, viz, Polystictus 

 abietinus and Lenzites sepiaria. 



(8) No definite conclusions could be reached concerning the prin- 

 cipal fungi which ret the bottom of the piles, since but few sporo- 

 phores of such fungi were found. 



(9) Xone of the main fungi concerned in rotting either the oak 

 or the pine slash in Arkansas produce heart rots in living trees. 



