11 
Table I. Abstract of Coolidge Experiment, 1904. 
(Planted May 13-17 and May 25; examined June 10.) 
Plat A 
Plat B 
*Plowed (1), harrowed (2), 
cultivated (9) 
75 hills examined 
*Plowed (1), disked three 
times (3,4,5), harrowed (6), 
cultivated (7), harrowed (8) 
225 hills examined 
Percent. 
of 
hills infested 
NumtSer of 
insects per 
hundred hills 
Per cent. 
of 
hills infested 
Number of 
insects per 
hundred hills 
Ants 
Aphids 
28 
17 
2263 
858 
10 
3 
185 
79 
1. Plowed May 14 to 16. 2. Harrowed May 17. 3. Disked May 18. 4. Disked May 21. 
5. Disked May 25. 6. Harrowed May 25. 7. Cultivated May 28. 8. Harrowed May 30. 
9. Cultivated June 9. 
The Harvel Experiment. (Table II.). — In the second experi- 
ment, made on the farm of Mr. A. T. Doerr, near Harvel, in Chris- 
tian county, a field of nine acres was divided into two parts, an 
experimental plat of three acres (Plat B) and a check plat (A) 
of six acres. In this field also the experimental plat consisted of 
thirty-two rows eighty rods in length. 
The check plat (A) received no treatment until June i, when 
it was spaded and harrowed. It was planted June 2 and harrowed 
June 13, the inspection being made the following day. On the 
experimental plat the stalks were harrowed down, raked, and burned 
May 13, the ground was plowed May 23, harrowed May 25, 
"spaded" on the 26th, and harrowed again on the 28th. At this 
time the field was practically free from weeds. On the 29th it 
rained all day, the first rain since the ground was plowed. This plat 
was spaded and harrowed June i and 2, and planted on the latter 
day. Rain followed on the 3d day of June, and the weather was wet 
until the 9th. The plat was rolled and harrowed on the nth and 
cross-harrowed on the 13th, the inspection following the next day. 
In this case it will be noticed that the whole field was planted at the 
same time. 
The harrowing to break down the stalks could scarcely have dis- 
turbed the ground sufficiently to interfere with the operations of 
the ants, and in a comparison of the plats that item may best be 
omitted. The difference in treatment is thus reduced to once plowing, 
once spading, harrowing three times, and rolling once, and to this 
♦Figures in parentheses refer to dates g'iven at bottom of table. 
