Feb., 1925] PROGRESS OF AGRICULTURAL EXPERIMENTS 19 



large to draw definite conclusions regarding the relative effects of the different 

 treatments. Very large increases have been obtained upon the treated plats 

 compared with an adjacent check plat which was left untouched. The check 

 plat yielded 335 pounds of hay per acre, while the treated plats ranged from 

 2124 to 4866 pounds per acre. 



Studies Upon the Lime Reqtiirements of New Hampshire Soils. 



The work upon this project was continued by Dr. Kraybill in co-operation 

 with the county agents along the same lines as the past three years. The 

 county agents take the samples of soil which the farmers wish to have tested, 

 fill out description sheets giving the location and characteristics of the soil and 

 send them to the department. The soils are tested by the department as soon 

 as they are received and the results reported to the county agents, so that they 

 are available for the immediate use of the farmer. These samples of soils are 

 preserved carefully and kept for future studies. During the past season 359 

 samples sent in by the county agents were tested, and in addition about 150 

 samples sent in by individual farmers. 



The Stalk Borer. 



The stalk borer, Papaipema nitela Guen., has been relatively abundant in 

 New Hampshire for a number of seasons. As opportunity offered, observa- 

 tions on its habits have been made in connection with other work. In the 

 beginning of 1923 a definite study of this insect was approved, to be carried out 

 by P. R. Lowry (Entomology) under the supervision of W. C. O'Kane. 



Observations of the larvae in 1923 appear to point to the existence of at 

 least seven larval instars. These observations need amplification and verifi- 

 cation. The first pupa was found August 16, and the last pupa September 3. 

 The pupal period ranged from 28 to 36 days. The first adult emerged Septem- 

 ber 18, and the last adult September 30. Adult male moths lived from 22 to 

 28 days, and adult female moths from 19 to 26 days. The number of eggs 

 deposited by a female moth range from a minimum of approximately 100 to a 

 maximum of nearly 500. 



Of the larvae collected in the field 11.76 per cent were parasitized by species 

 of the family Tachinidae. 



Black Flies. 



The large number of collections and records secured by W. C. O'Kane in 

 several seasons' work with black flies have been in process of study, identifica- 

 tion and classification in the course of the year. These are disclosing the fact 

 that there is apparently one species of black fly in New Hampshire that has not 

 hitherto been described or known to science, and that there are several species 

 that have not hitherto been of record as occurring within the state. 



The records and collections represent many observations maintained- at 

 frequent intervals at more than thirty observation points in various parts of the 

 state. The records include height of water in the streams as well as species 

 found on the dates when observations have been made. 



AU of this data is in process of correlation and is expected to yield a study in 



