1911.1 PUBLIC DOCUMENT — No. 31. 35 



EXPERIMENTS RELATING TO THE PREVEN- 

 TION OF THE CLOGGINU OF DRAIN TILE 

 BY ROOTS. 



BY G. E. STONE AND G. H. CHAPMAN. 



Fur the past three years experiments have been carried on in 

 our conservatory for the purpose of studying the effects which 

 various antiseptic substances would have in preventing roots of 

 different kinds from entering drain tile. The clogging of drain 

 tile by roots is a serious matter, many drains being rendered 

 useless in a short time. The only remetly in such cases is to dig 

 up the tile, clean it out and lay it over again. This is expen- 

 sive and unsatisfactory in any case, particularly so with sewer 

 pipes or the drainage tile imder steam-heating conduits. 



Our experiments were carried on in different ways. In one 

 series we buried 3-inch Akron tile vertically in boxes contain- 

 ing soil. The lower ends of these tile were cemented and the 

 tile filled with water to the joints. The joints were then calked 

 with various antiseptically treated fibers, and the antiseptic 

 substances with which the joints were treated proved quite 

 efi'ective in preventing the access of roots to the tile. 



Another method consisted in gTOwing various plants in small 

 pots, the bottoms of which were filled with chemically treated 

 fibers. The pots were then filled with soil and planted with 

 different seeds. It is well known that plants when grown in 

 small pots soon fill the soil with roots, which seek new sources 

 of supply by passing through the hole at the bottom of the pots. 

 Our experiments were arranged in such a way that the roots, 

 in. order to accomplish this, would have to pass through or 

 around the chemically treated fibers, and the ability of these 

 fibers to ]irevent root development constitutes a test of their 

 efficiency. This method ]iroved quite satisfactory. After a 



