18 



N. H. AGE. EXPERIMENT STATION 



[Bulletin 204 



earth, as it was removed, was treated 

 with Phinotas oil and water and carted 

 away to a dump. 



In this work, and in the treatment 

 of termites found under stones at the 

 old barn cellar and in similar places, 

 Phinotas oil was used because it mixes 

 promptly with water and has strong 

 insecticidal properties. It is easily 

 prepared for use simply by pouring 

 the oil into water. Water was used 

 in such amount as to give a dilution of 

 one-half of one percent. It was found 

 that this dilution readUy killed term- 

 ites. So far as experience in this place 

 is concerned, the ground so treated 

 remains unsuitable to termites for a 

 considerable or. perhaps an indefinite 

 period thereafter. 



The trench next to the foundation 

 walls was fiilled with cinders. The in- 

 tent of this was to provide next to the 

 walls a band of material which pre- 

 sumably the termites would find less 

 suitable than earth containing organic 

 matter. It was expected, also, that 

 the cinders would remain rather dry 

 throughout the season when the term- 

 ites were most active and, therefore, 

 would offer a medium not well adapted 

 to their galleries. The bottom of the 

 trench was treated with Pliinotas oil and water before the cinders were placed 

 in it. Up to the present time no further evidence of termites has been 

 discovered in the trench or in or on the foundation walls, although through- 

 out the two seasons that have followed many termites have been found 

 short distances away. 



It was thought that the work of fighting the pests in the grounds outside 

 the building would be facilitated if it were possible to discover the source or 

 sources from which they were working toward the building. In order to 

 attempt this, sm all blocks of pine wood, four of five inches square, were placed 

 on the ground, every three or four feet all the way around the entire circum- 

 ference of the buildiag, two or three feet away from it. These blocks were 

 turned over and examined every two or three days. The result of this was 

 the disclosure that by far the greater part of the entire area surrounding 

 the building appeared to be supporting termites. They were especially 

 numerous in the rear of the building on the north side of the women's pa- 

 vilion and on the south side of the men's pavilion, but they were found 

 scatteringly in other places. It was not possible to determine from what 



Fig. 4. Diagrammatic plan of 

 supplementary heating coils installed 

 in basement of administration build- 

 ing. 



