562 Report oF THE HortTICULTURIST OF THE 
experiments, personally attended to the preparation of the soil 
and assisted in all the details of the experiments at his place.. 
The ground selected at Peruville served as a dooryard years 
ago. It has been planted to potatoes repeatedly but finally has 
been abandoned for this purpose because the crops were inyari- 
ably so scabby as to be nearly or quite unmerchantable. 
Similar experiments were carried on at this Station on more 
favorable ground which was not known to be infected with the 
acab. By means of these duplicate experiments it was possible to < 
eompare the proposed remedies on favorable and unfavorable 
soils. Two methods of using the remedies were tried, namely, 
(1) by soaking the seed before planting, and (2) by spraying the 
soil and seed at planting time. In every experiment and in the 
rows left untreated for comparison scabby tubers were used for 
seed so as to give the treatments a more thorough test. 
These experiments show that under certain conditions potato 
scab can be largely prevented in a practical way. On badly 
infected ground, on “scabby ground” if you please, no treatment 
was of any practical benefit. The failure was not in every case a 
complete one, but no practical advantage resulted from the treat- 
ment. On the more favorable soil at the Station a decided 
advantage resulted from some of the treatments, chiefly from zine 
sulphate (white vitriol), iron sulphate (copperas) and mereurie 
chloride. These investigations confirm in a measure both the 
work of Bolley* who found beneficial results from soaking the 
seed in mercuric chloride, and of Kinney§ who found that Bor- 
deaux mixture sprayed on the soil and seed at planting time — 
lessened the amount of scab in the crop. 
It should be borne in mind that lessening the amount of scab 
on the immediate crop is not the only advantage arising from 
_ treating the seed with fungicides, for if the fungus once becomes 
established in the soil it may live there from year to year and 
it is therefore wise to take care not to introduce the disease into 
uninfected soils. Tubers selected from a scabby crop, though 
apparently smooth, may contain microscopic germs of the dis- 
ease and ought therefore to be » antes either by apr, or 
* Bull. 4, North Dakota Expt. Station, Dec., 1891. 
§ Bull. 14, Rhode Island Expt. Station, Oet , 1891. 



