October, '16] 



NITRATES IN ORCHARD SOILS. 



25 



Average Moisture atid Nitrates in Second Orchard, 1916. 

 Surface Soil. 



After small plats similar to the ones described in Plot 1 were 

 made on Row 4 determinations were made which gave the fol- 

 lowing results: 



Table No 16. 



No rains fell during the first few weeks of these observations 

 and the nitrates accumulated as the weeks progressed and formed 

 a rapidly ascending curve where the soil was stirred, but on Sept. 

 15, 1.42 inches and Sept. 18 1.10 inches of rain fell and the curve 

 drops down again as the nitrates had washed out. 



These results do not extend over as long a period as might be 

 desirable but from our experience over four years in the orchard 

 they seem to duplicate the results obtained there. 



EFFECT OF LIME ON NITRIFICATION. 



It has been shown a number of times that when lime is applied 

 to soil it will increase nitrification. Four years' results on a 

 cultivated orchard show a greater average amount of nitrates 

 recovered in the samples where the lime was applied. However, 

 nitrates are quite variable and seem to be readily affected by 

 weather conditions. Especially where fertilizers have been ap- 

 plied do we find irregularities apparently due to obtaining some 

 of the fertilizers in the sample occasionally. So that any par- 



