22 BULLETIN 108, U. S. DEPARTMENT OF AGRICULTURE. 



was alkaline, and one was neutral. Of the field soils which contained 

 the aldehyde, ten were acid, one alkaline, and one neutral. 



(6) In soils growing different crops. — Four of the soils which were 

 found to contain aldehydes were garden soils and had been used for 

 growing garden crops continuously for several years. One was a 

 greenhouse soil and had grown carnations and roses. Twelve of the 

 soils in which aldehyde was found were used for the growth of general 

 field crops. A rotation of several crops was practiced on most of 

 these soils. At the time the samples were collected three were in 

 grass, four were growing corn, three were growing cotton, one was in 

 wheat and one was fallow. These observations, together with the 

 fact that no aldehydes were found on other soils growing the same 

 crop, would seem to indicate that no close relation exists between 

 the crop being grown and the presence of aldehyde. 



EFFECT OF SALICYLIC ALDEHYDE ON COWPEAS, STRING BEANS, AND 

 GARDEN PEAS GROWN IN THE FIELD. 



The effect of salicylic aldehyde under field conditions was tested 

 on plots at the Arlington Experiment Farm, Va. Three crops, 

 cowpeas, string beans, and garden peas, were grown on the treated 

 soil during the summer of 1913. Adjoining each plot growing a 

 different crop, two check plots of equal size were planted with the 

 same crop. The area of each plot was one-fourth of a square rod. 



The soil on which the experiment was made is a heavy silty clay 

 loam, low in organic matter. The land was plowed early in May 

 and prepared for seeding with the above leguminous crops. Three 

 applications of salicylic aldehyde were made, the first on May 20, 

 one day before the crops were planted. The second application 

 was made after the plants were up, on June 5, the third on June 24. 

 Each application was at the rate of 35 pounds per acre, or 105 pounds 

 per acre in all. 



The salicylic aldehyde was applied by dissolving in water and 

 sprinkling the solution uniformly on the surface of the land before 

 planting and the soil cultivated thoroughly. After planting, the 

 second and third applications were made by sprinkling the solution 

 between the rows of plants, and the soil then cultivated. 



All of the three crops germinated uniformly. The untreated check 

 plots made the better growth from the very start. The effect of 

 the salicylic aldehyde was noticeable throughout the experiment. 

 The crops were grown to maturity and harvested. 



EFFECT ON COWPEAS GROWN IN THE FJEED. 



Both treated and untreated plots were sown to cowpeas on May 21, 

 1913, and the crop harvested on September 7, 1913. The cowpeas 

 on the salicylic aldehyde treated plot were much stunted in growth. 



