292 CONNECTICUT EXPERIMENT STATION REPORT^ I907-I908. 



cages is shown on Plate V, a., and a nearer view of a cage 

 with one side raised is shown on Plate V, b. 



Two cages were left as checks, and in four the soil was culti- 

 vated, once, twice, three and four times respectively. The 

 ground was stirred as thoroughly as possible with a spade to 

 a depth of at least four inches. All lumps were crushed, making 

 the cultivation probably more thorough than would be possible 

 with any of the ordinary orchard tools. The dates, number of 

 times cultivated, etc., are given in the following table : 



The cultivation seemed to slightly delay the development of 

 the insect and on June 14th more adults had emerged in the 

 check or untreated cages than in the cultivated; but at the next 

 visit there was very little difference. Slight difference was noted 

 between the cages cultivated a different number of times, and 

 even in the cage where the soil was cultivated four times, which 

 would not be practicable in orchard work, the treatment did little 

 more than to retard the development of the insects. 



During the latter part of May the orchard was plowed with a 

 light gang plow, turning three furrows from two and one-half 

 to three inches deep ; this turned up many larvae, but there were 

 still many left below the bottom of the furrow, and the majority 

 of those that were plowed up emerged, as was shown by the 

 numerous exit holes. 



Carbon Bisulphide. 



Carbon disulphide has long been used in France against the 

 grape phylloxera. The substance is injected into the soil around 

 the vines, and the liquid evaporates, though much more slowly 



* No. 8 was on rather higher ground than the other check, No. 3. No. 

 was a tree in row opposite No. 8. 



