120 BELL SYSTEM TECHNICAL JOURNAL 



for termite attack. Six hundred 8-inch lengths were dried in the oven in 

 the laboratory at 105°-110°C. and then weighed. The specimens were 

 then shipped to Gulfport, Mississippi, and distributed throughout the test 

 plot in April. Each eight-inch specimen was buried in the soil until the 

 end of the specimen was even with the level of the soil. At the end of 

 each two-month period subsequent to exposure about 80 specimens were 

 removed, brushed free of dirt and mycelia, oven-dried, and reweighed. 

 In order to study decay during the winter months, 150 additional pieces 

 were planted in October; seventy-five of these were removed after four 

 months and the rest after sLx months exposure. 



From Fig. 5 it is evident that in the field test the loss in weight due to 

 decay was far less than that obtained in the soil test in the laboratory. 

 The maximum amount of decay in the field after two months was as high 

 as 10% in only two out of the 81 samples exposed; after four months it was 

 19%, after six months 30%, after eight months 20%, after 10 months 30%, 

 and after 12 months 50%. While the maximum percentage loss applies 

 only to one specimen in each case, in general the average percentage losses 

 noted in the figure were far below these figures. Therefore, decay in the 

 field does not approach in uniformity and rapidity that occurring under 

 controlled conditions in the laboratory. 



Experiment at Chester, New Jersey, Using Various Nutrients: 



Another field experiment was devised in which an attempt was made to 

 increase the rate of decay by using nutrient materials and salts which would 

 change the pH of the soil. SL\teen-inch untreated sticks were selected for 

 uniformity within a very narrow density range and exposed in each of six 

 specially prepared plots in northern New Jersey. The ground was first 

 plowed, then harrowed and raked free of stones so that the soil in all plots 

 was nearly uniform before treatment. Then fifty sticks were buried to a 

 depth of 7 inches in each plot in rows of five, with two feet between each 

 row and one foot between the sticks in each row. The plots were treated 

 as follows: 



Plot No. 



Treatment 



Control 



Barnyard manure 



5 pounds lime 



5 pounds commercial fertilizer (5-10-5) 



5 pounds aluminum sulfate 



Nutrient solution* 



* Containing the following minerals dissolved in ten gallons of water, then sprinkled 

 over the entire plot: 



