EXPERIMENT STATION BULLETINS. 181 



pests to combat. The writer has made an effort to select a spray that 

 will kill the greatest number of those hit, trusting to the operator to hit 

 as many as possible and to repeat the application when necessary. 

 Others have found it practical to place a low tent over the plants, and 

 to fumigate with burning tobacco stems and other agents. Such fumi- 

 gation has given partial success, but seemingly is little, if at all, 

 superior to the sprays. The cost of fumigation is unquestionably 

 greater. The spray that gave the best results with us was whale-oil 

 soap kerosene-emulsion, with Pj^rethrum added. (See directions for 

 preparing insecticides.) This was diluted ten times. We succeeded in 

 killing about 99 per cent of the lice, in one trial, doubtless all that were 

 hit. In order to apply this spray with sufficient thoroughness, a knap- 

 sack pump was used. This was fitted with a short extension, about 

 three feet long with a Vermorel nozzle set at right angles to the exten- 

 sion, making it easy to apply the spray sidewise and upward from 

 beneath. 



As stated, the lice usually start from one or two vines in a field. 

 Careful watching will reveal these centers of infestation and prompt 

 treatment should check their spread in the beginning. Of course it will be 

 necessary to repeat the spray as often as the lice appear. As in the 

 case of the lice on cherry, the difficulty lies in reaching the lice and not 

 in making a spray that will prove effective. 



Squash-bug {Anasa tristis). 



Everyone knows the large black stink-bug or squash-bug of the garden 

 and field. All of us have tried to kill it by sprays, dust-baths and what 

 not, but still the stink-bug flourishes. There seems to be no wash or 

 powder that will kill the bug without at the same time, killing the 

 plants. 



The eggs of these marauders are red in color, and quite large, they 

 are laid in patches on the leaves, for the most part, on the underside. 

 The young bugs that come from these eggs resemble the adults very 

 iinich except in their proportions and in size, although of course they 

 lack the wings. Not only do the bugs attack the vines, piercing them 

 with their long beaks, and extracting the sap, which alone is enough 

 to seriously injure the plants, but, at the same time, they carry the germs 

 of disease from one plant to another, thus inoculating healthy plants 

 with the wilt, and possibly with other diseases. 



REMEDIAL. 



Plants grown under mosquito-netting of course escape the bugs, but 

 such a measure is very expensive except in unusual cases. 



Clean culture. — In the autumn after the crop is secured, the bugs con- 

 tinue to feed on the old vines for some time before the vines dry up 

 and die. The writer has collected large numbers in such situations. 

 Young bugs, old bugs, and bugs half-grown. It is these young and 

 vigorous bugs that hibernate and start new generations in the spring. 

 The remedy is obvious — destroy all old vines, squash, pumpkin, cucum- 



