HARMFUL EFFECTS OF ALDEHYDES IN SOILS. 
23 
The appearance of the plants on June 27 is shown in Plate VII, figure 1 . 
The four rows of plants on the left are growing on the treated plot 
and the four rows on the right on an untreated plot. It is evident 
that the salicylic aldehyde is interfering with the proper development 
of the young plants. The effect became even more marked as the 
plants approached maturity. When mature, the peas were picked 
from the vines and weighed. After drying, the peas were shelled 
and measured. The vines themselves were cut and their weight 
taken. After curing, the weight of the dry hay was recorded. In 
Plate VII, figure 2, are shown the vines and peas as gathered from 
the check plot and from the salicylic aldehyde treated plot. The 
effect of the salicylic aldehyde in depressing crop yields is apparent. 
In Table XI are given the results obtained in this experiment with 
salicylic aldehyde on cowpeas. The results are given as obtained 
from the individual plots and also in terms per acre: 
Table XI. — Yield of cowpeas as affected by salicylic aldehyde in the field. 
Yield per plot. 
Yield per acre. 
Treatment. 
Vines. 
Pods. 
Vines. 
Pods. 
Green. 
Cured. 
Green. 
Cured. 
Pounds. 
28.0 
23.0 
Pounds. 
10.0 
8.5 
Pounds. 
6.6 
5.6 
Tons. 
8.96 
7.36 
Tons. 
3.20 
2.72 
Tons. 
2.11 
Check b 
1.79 
25.5 
16.0 
9.3 
4.3 
6.1 
3.5 
8.16 
5.12 
2.96 
1.38 
1.95 
Salicylic aldehyde 
1.12 
Difference 
9.5 
5.0 
2.6 
3.04 
1.58 
.83 
From the table it will be seen that the average yield of green vine 
and pods on the check plots was 10.11 tons, and on the salicylic 
aldehyde plot it was only 6.24 tons, making a total decrease of crop, 
3.87 tons, or 38 per cent. The yield in pods alone was reduced 43 per 
cent, and in vines alone, 35 per cent. The cured hay, minus the pods, 
was reduced in yield as much as 1.6 tons per acre, a decrease of 50 per 
cent. 
EFFECT ON STRING BEANS IN THE FIELD. 
The string beans were less affected by the salicylic aldehyde than 
the cowpeas, and also less than the garden peas. The seeds were 
sown May 21; they germinated well, and a good stand was secured. 
As the crop grew it became apparent that there was a difference in 
the growth of the treated plots and the untreated, but it was not 
as marked as with the cowpeas. On July 22 the crop was harvested 
and the weight of green vine and beans obtained separately. The 
results are given in Table XII, and a photograph of the harvested 
crop is shown in Plate VIII, figure 1. 
