82 REPORT OF THE BOYANIST OF THE 
THE THREE YEARS’ EXPERIMENTS—1898-1900. 
Objects of the Experiments. 
In the experiments of 1897 the best results were obtained 
where the smaller quantities of sulphur and lime, 125 and 256 
pounds per acre, were used. This fact suggested the idea that 
perhaps the larger quantities of the mixture were in some way 
injurious to the growth of the plants. When the treatment is 
applied every year for a series of years a considerable quantity 
of the sulphur and lime must accumulate in the soil. Now the 
question arose, What will be the effect of repeated applications 
of sulphur and lime? If the accumulation of these substances 
in the soil injures the growth of the plants perhaps it will be 
better to use even smaller quantities than 125 pounds per acre. 
On the other hand, if such accumulation in the soil is not detri- 
mental to the plants, may we not expect better results with the 
smut after the soil once becomes thoroughly impregnated with 
the chemicals? Hence, one object of these experiments was to 
determine the effect of repeated applications of the sulphur and 
lime. 
The application of sulphur and lime in the row inyolves con- 
siderable extra labor. Why not save this labor by applying the 
mixture broadcast? Hence, asecond object of these experiments 
was to determine the effect of broadcast applications of sulphur 
and lime. 
For convenience we will hereafter call the experiments in 
which the chemicals were applied in drills Series I, and the ex- 
‘periments in which they were applied broadcast Series II. 
Series I.—Sulphur and Lime in Drills. 
Plan of experiments.—In the work of the previous two years 
we learned that onion smut is rarely equally destructive to all 
parts of a field. Often there are great differences in a distance 
of a few feet. In order to eliminate from an experiment the 
effect of such inequalities in the soil the plats must be long and 
narrow and duplicated several times. But since it was planned 
to continue the experiments for three years the plats must be 
