EXPERIMENT ON SOIL IMPROVEMENT. 703 
a mixed stable manure at the rate of 12 tons or 5% cords per 
acre. It will be seen that the valuation of the materials used 
on these two plots is nearly the same per acre, if the manure 
is reckoned at $3 per cord. 
Plot M has had no fertilizer for the past two years, but 
whenever practicable some leguminous crop has been grown 
between the seasons of the regular crops from year to year for 
the purpose of plowing under. Clover was grown for this pur- 
pose after the corn crop of 1899 and was plowed under in the 
spring of Igoo. 
Plots N and P are designed to be similarly fertilized by the 
use of a mixture of South Carolina acid phosphate and muriate 
of potash. ‘This mixture is used on each of these plots in the 
following proportions per acre: acid phosphate, 500 pounds; 
muriate of potash, 200 pounds. On plot N it is planned to 
grow, for plowing under between the times of the regular 
crops, some cereal crop, like rye. This crop followed the corn 
crop of 1899 and was plowed under before the crop of 1900 
was planted. On plot P the same fertilizers have been used as 
on N, but a legume has been grown to plow under in place of 
the rye on plot N. Clover was grown for the purpose after 
the corn crop of 1899. 
Whenever possible, it is the plan to grow a crop for plowing 
under on plots M, N, and P, between the crops of the regular 
rotation. ‘The experiment for 1899 with corn was necessarily 
a preliminary test, as it was not practicable to grow a catch crop 
for plowing under previous to starting the experiment in the 
spring of 1899. Alsike clover was, however, sown amongst 
the growing corn on plots M and P late in July, 1899. The 
clover made a fair growth the fall of that year and early in the 
season of 1900. It was about three inches high and covered 
the ground in a thick mat when plowed under, April 12, pre- 
paratory to planting the potatoes. Plot N was sown to rye 
October 10, 1899, and this was plowed under at the same time 
that the clover was on plots M and P. The rye was about 
three feet high and in bloom when plowed under. 
The yield of potatoes for rg00. ‘The crop made a vigorous 
growth on all of the plots. The potato vines were sprayed 
twice for the blight, with Bordeaux mixture. The plants 
