



_ the Peruville experiments: 
eR 
— ; 
New Yorx AGRICULTURAL EXPERIMENT STATION. 569 
Experiments in which there was more scab in the treated than in 
the untreated rows are indicated by a *. It will be noticed that 
this occurred in none of the Station experiments and in but few of 
Taare I, 










SERIES A. SERIES B. 
o wi 2 >. M4 
gg |) Be) wee | ge | Ba i Gee 
| 38 | 58 | S38) BE | BS | Bae 
by ae a < Aan ee ei Hh 
a@ Copper sulphate.... ...| + | OL A Wea +. | AOLB ees 
6 Iron sulphate .......... QL RB ON Osh eB hae ae 
¢ Zinc sulphate .......... B70 V6 18 18 Pea ene 
d Kau Celeste ........ Hii ed tet ap Up ea BE kee t 
é Bordeaux mixture ...... DEO BeBe 2) E Ol a dy Mea 
J Mercuric chloride ...... 27.4 GOS ols MOBS ck Se BO ae 
g Ammoniacal solution of | 
copper carbonate...... Oeste Be a? gan Ry Maa Aa + | 0.5 0.5 

_ Taking all things into considerations it appears that in series A 
where the soil and seed were sprayed, an average of all. experi- 
ments shows that the use of mercuric chloride gave greatest — 
freedom from scab, but in the Station experiments alone where 

+‘Results unfortunately vitiated. t Killed by the treatment. | See note Table I. 
§ Before attempting to draw any conclusions from these tables it will be well 
to examine the first table with reference to the variation in the amount of 
scab in the untreated rows. It will be noticed that the amount of the scab in 
the untreated plots at the Station varied from 40.6 per cent. to 63.8 per cent. 
in series A and from 34.9 per cent. to 49.5 per cent. in series B, notwithstand- 
ing the fact that they were very near to each other. The average of the 
untreated plots in all experiments as seen by the same tables shows a variation 
from 63.8 per cent. to 81.9 per cent. in series A and from 66.2 per cent. to 71.4 
per cent. in series B. Probably this variation in the amount of scab in the 
untreated plots is partly due to the varying scabbiness of the seed and to the 
varying amounts of the scab fungus present in the soil. It ismecessary to bear 
these things in mind when considering the comparative merits of the different 
fungicides as apparently shown in these tables. On the other hand it may be 
said that the treated rows were always compared with adjacent untreated 
“rows so as to avoid, as far as possible, untrustworthy comparison ; this 
_ together with the fact that the experiments were all duplicated and some in 
series A were tested in three separate plots, and that series B also duplicated 
series A in the kind and strength of the fungicides used, renders the results of | 
considerable value. - | 
72 
