TO MAKE FLY-PAPER. 241 



AFTEnxoox Session. 



The Board rc-assembled at two o'clock ; and, before peter- 

 ing upon the regular programme for the afternoon, Mr. Ware 

 described his method of dealing with the canker-worm by 

 putting strips of tarred paper around the tree, about ten inches 

 wide, Avhich he fastened by a string at the top and bottom, 

 and covered with the residuum of kerosene, in the fall and 

 winter, when the ground is open so that the grubs come out 

 and go up the trees, and also in the spring as soon as the 

 ground opens. 



Dr. Fisher. I think I can suggest a better remedy for the 

 canker-worm than Mr. Ware has found. You all know what 

 fly-paper is, and you can just as well apply that to your trees 

 as not. I will tell you how to make it. Take linseed-oil 

 one part, and rosin four parts : if it is too stiff, use a little 

 more oil ; if it is too limpid, a little less. That is in every- 

 body's possession. Melt together, and apply warm. 



The Chaiiima^t. The Committee of Arrangements, in 

 arranging the programme for these meetings, were very care- 

 ful to reserve the best for the last ; and we have this after- 

 noon a subject which will be interesting to all farmers, 

 vitally so. I have the pleasure of introducing Professor 

 Stockbridge of the Agricultural College at Amherst. 



EXHAUSTION OF SOILS BY THE GROWTH OF PLANTS. 



DY PKOFESSOK LEVI STOCKCKIDGE. 



The subject which has been assigned to me yon have 

 on 3'our programme as " The Exhaustion of Soils by the 

 Growth of Crops." Now, I apprehend that the expression 

 " exhausted soil" is often used with little precision of mean- 

 ing, and sometimes, perhaps, in ignorance of what constitutes 

 the real difference between exhaustion and fertility. There 

 is an important sense in which an exhausted soil is an im- 

 possibility. Plants are made up out of the material of the 

 soil. Nearly all the soil, from its surface down to the bed- 

 rock, however deep the mass may be, is capable, in answer 

 to the action of natural law, of being transformed from the 

 soil-form to the plant-form : therefore we cannot say that 

 the soil is exhausted until the entire mass has passed 



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