208 
Table 2.— Showing number of plants affected with rust on Mag 6 —Continued. 
SERIES IV.—MISCELLANEOUS TREATMENTS—Continued. 
Plat. 
Method of treating. 
No. of plants 
showing rust. 
Total 
plants 
showing 
rust. 
Origi¬ 
nal. 
Dupli¬ 
cate. 
Origi¬ 
nal. 
Dupli¬ 
cate. 
72 
162 
Seed immersed 15 minutes in hot Avater, soil 
treated with ferrous sulphate, 2 ounces to 20 
ieet of row. 
0 
0 
0 
73 
163 
Untreated... 
5 
0 
5 
74 
164 
Seed treated 24 hours in 10:100 solution of ferrous 
sulphate, soil sprayed with same preparation, 
plants sprayed every 10 days with 4 ounces to 
1-gallon of water. 
0 
0 
0 
75 
105 
Untreated..*. 
10 
0 
10 
76 
166 
Seedimmersed 24 hours in ammoniacal solution, 
plants sprayed every 10 days with same prep- 
aration. 
0 
0 
0 
77 
167 
Untreated. 
25 
0 
25 
78 
108 
Soil treated with salt, T \j ounce to 10 feet of row.. 
8 
0 
8 
79 
169 
Untreated. 
20 
0 
20 
80 
170 
Soil treated with salt, A, ounce to 20 feet of row.. 
35 
0 
35 
81 
171 
Untreated. 
17 
0 
17 
82 
172 
Soil treated with copper sulphate solution, 13£ 
ounces to 134 quarts of water per plat.. 
nearlv dead. 
83 
173 
Untreated. 
0 
0 
0 
84 
174 
Plants sprayed with cupric hydroxide mixture 
every 10 days. 
0 
0 
0 
85 
175 
Untreated. 
0 
0 
0 
In a study of tlie foregoing table one of the most striking things no¬ 
ticed is the absence of rust from nearly all the duplicate plats. It 
should be remembered that all of these were planted from a we eft to 
teo days later than the originals; in point of growth they were at least 
this much behind the latter at the time of the count. The only sug¬ 
gested explanation of lack of rust at this time is upon the assumption 
that the plants had not reached the proper age for infection. If this be 
true, as subsequent observations would seem to indicate, the fact has 
considerable practical value, as it would point to the possible exist¬ 
ence of what may be called a susceptible period, at which time a special 
effort in the way of protecting the plant would be highly important. 
If such a period really exist the earlier treatments would be of little 
use and consequently might be abandoned. Looking over the soil 
treatments, it appears that in no case did they have any appreciable 
effect on the prevalence of rust. The 12 plats treated gave 304 plants 
affected, while the untreated showed 354 plants. 
In the case of the plats where seed treatments were made, 92 plants 
were found affected with.rust, while the 7 untreated plats used as con¬ 
trol gave only 24 plants. The plats sprayed and dusted showed some 
interesting results. Ho rust whatever was found on Ho. 40, sprayed 
every ten days with Bordeaux mixture, nor could the slightest trace of 
the fungus be discovered on jdat 42, sprayed with ammoniacal solution 
every ten days. The untreated plats adjoining Hos. 40 and 42 showed, 
respectively, 42 and 58 affected plants. The plats sprayed with Bor¬ 
deaux mixture and ammoniacal solution every twenty days were notin 
as good condition as those where the ten-day treatments were employed. 
Taking the sprayed and dusted plats as a whole, there was no striking 
