It will be noticed from the above table that the wheat germinated 

 much more quickly than the corn, and that the injurious effect of the 

 blue vitriol was somewhat greater. 



A more severe test was made with the same solution of blue vitriol 

 (5 pounds to 10 gallons) upon the same sample of wheat by allowing 

 about a pint of the seed to remaiiuitt-thfi^olution for thirty-nine hours, 

 and the same amount in water for an equal length of time. At the end 

 of that time the water was turned off, a part of the seeds of each lot 

 kept damp by blotting paper, and the remainder planted. Nearly all 

 the seeds which had been in water grew well, but none of those which 

 had been in the solution of blue vitriol. 



The next trial was of a solution of copperas or green vitriol upon 

 corn. Copperas is used as a fertilizer, as a fungicide, and as an insecti- 

 cide. Griffeth in his treatise on manures (London, 1889) after treating 

 extensively of its use as a fertilizer, mentions its value as a fungicide, 

 and states (page 302) that all fungous diseases of wheat may be destroyed 

 by a top dressing of 50 pounds of copperas per acre, or by soaking the 

 seed in a 1 per cent, solution. 



In Bulletin 5 of the Iowa experiment station, on page 164, reference 

 is made to the use of copperas as a remedy for cut-worms, the amount 

 recommended being a little over 1 pound for a bushel of seed, with 

 water sufficient to cover the grain. 



This strength was taken for the trial, comparison being made with 

 a much stronger solution, and also with pure water. The trial was made 

 in duplicate, one set in the green-house, the other in the open ground, 

 the other conditions being the same. The seed was soaked in each 

 case twenty-four hours, and planted May 17, 100 kernels in a place 

 as in the other tests. The examination was made daily, and, as in the 

 other cases, as nearly as practicable at the same hour, usually at 6 a. 

 m. The record begins on the day upon which the first plants appeared 

 above ground. 



IV. — Copperas upon corn. 



Date. 



(a) In the green-hoase. 



■Water. 



Copperas, 

 1 poand 



per 

 bushel. 



Copperas 



veiy 

 strong. 



(6) In the open ground. 



Water. 



Copperas, 

 1 pound 



per 

 bushel. 



Copperas 



very 



strong. 



May 24 

 May 25. 

 May 26 

 May 27. 

 May 28. 

 May 29. 

 May 30. 



1 

 20 

 59 



73 

 74 



79 

 79 



