CHEMICAL DEPARTMENT. , 175 



and then the trees fall victims to these ruthless suckers. I have seen trees 

 in all parts of our State thus enfeebled or destroyed. 



The old remedy, soft soap, or a strong solution of the same, will surely 

 vanquish this enemy if it is applied to the trunk and main branches in 

 early June and again three weeks later. I have proved the efficacy of this 

 treatment over and over again. The trees at once put on new vigor, and 

 in a short time only dead lice could be found. To apply this specific I 

 know of no better way than to use a cloth and scrub by hand. To be sure 

 we can, if dainty, use a brush like a shoe-brush, but I like to go at it with a 

 good cloth, when, with sleeves rolled up, I make pretty sure that no louse 

 escapes. If this carbolic acid solution is used, caution is required that we 

 do not sprinkle the foliage, or the leaves will be killed. 



For the past few years I have changed the substance by adding crude car- 

 bolic acid, which I think improves it, especially if but one application is to 

 be made ; and we know that at this busy season the second application is 

 apt to be neglected. 



I heat to the boiling point one quart of soft-soap to two gallons of water, 

 and while still hot thoroughly stir in one pint of crude carbolic acid. This 

 may be applied as before. This carbolic acid mixture retains its virtue, I 

 think, longer than does the soap alone, and so is especially desirable when 

 but one application is to be made, as described above. 



Like the arsenites, so this carbolic acid and soap mixture is of triple 

 value. Not only does it kill the dreaded lice but it also keeps off the borers, 

 which are also serious pests in the orchards of Michigan. The old borers, 

 Saperda Candida, and ;S'. cretata, are quite common and destructive in our 

 State, while the Big-headed Borer, Chrysohothris femorata, is even more 

 prevalent and harmful. I have demonstrated beyond question that these 

 enemies are surely kept away by the same treatment, applied at the same 

 time for which we use it to ward off the scale lice. No v.'onder, then, that 

 our trees put on such new life and vigor after this annual scrubbing. 



In each of these remedies, then, not simply two but several birds are killed 

 by the self same stone. It is to be hoped that many of our fruit growers 

 will throw it, and thus secure fairer fruit, and save much to our State. 



A. J. COOK, 

 Agricultural College, [ Professor of Zoology and Entomology. 



May 1, 1886. 



No. 15.— CHEMICAL DEPARTMENT. 

 MANURIAL VALUE OF ASHES. 



The value of ashes for manure is a subject ot inquiry among farmers and 

 fruit growers, and has given rise to so large a correspondence with this De- 

 partment that I have concluded to group my answers into one general reply 

 in the form of a bulletin. 



Tables of analyses of the ashes of plants of great scientific value can be 

 found in the books, especially in Prof. Johnson's "How Crops Grow;" but 

 the very nicety of these analyses, and the careful exclusion of all foreign and 

 accidental substances usually present in ashes as we find them on the farm or 

 at the factory, render such analyses of less practical value to the farmer and 



