162 Forty-second Report on the State Museu3i. [20] 



work. Suitable pumps may be bad of tbe Field Force Pump Com- 

 pany, of Lockport, N. Y. ; Goulds Manufacturing Company, at Seneca 

 Falls, N. Y. ; Rumsey & Company, also of Seneca Falls, and P. C. Lewis, 

 of Catskill, N. Y. Each of tbe above firms will readily send illustrated 

 circulars giving style and prices of their pumps and spraying appara- 

 tus from which selection may be made. 



3. The right manner of applying the insecticide, when employed 

 against plant-lice, is, that it shall be made to reach every insect. This 

 is not essential when the canker-worm and other caterpillars which 

 feed by means of cutting jaws upon the poisoned foliage are to be 

 killed. The finer the spray can be delivered from the nozzle, the 

 more effective is it against the aphis. Other advantages of fine 

 spraying are, economy in the material used, and, in the case of arsen- 

 ites, less danger of poisoning stock that may enter the orchard before 

 heavy rains have occurred, by the dripping of the liquid from the 

 trees upon the grass. If London purple be used instead of Paris 

 green (with which it is equally effective) of a dilution of one pound to 

 150 gallons of water, and the spraying be discontinued as soon as the 

 trees commence to drip, danger in this direction will be very little, 

 if any. 



Tobacco Dust fob Aphis Attack. 



Mr. Peter Henderson, the experienced and well-known horticultur- 

 ist of Jersey City Heights, N. J., has lately published his method of 

 dealing with the plant-lice or Aphides that are so injurious to roses, 

 grapevines, chrysanthemums, and hundreds of other species of plants 

 cultivated both in the open air and under glass. While the antidote 

 used by him is not new, his method of application may not be gener- 

 ally known. It is as follows: 



"A certain remedy is to apply tobacco dust with a bellows when the 

 leaves are wet, at/least once a week — twice is better. We have used 

 this as a prevei^ve remedy for many years with the most excellent 

 results on all plants subject to aphis. 



" The main reason why remedies fail is owing to the fact that they 

 are rarely long enough persisted in. One or two applications may 

 check the trouble, but will check it only. My rule for these pests is 

 prevention, which need never fail, if the remedy is steadily applied. 



" In our new practice every kind of plant that we know to be liable 

 to be attacked by aphis is dusted over with tobacco dust twice each 

 week from June to October. Of course at such times as the roses or 

 chrysanthemums are in fiower, or when the fruit of grapes is ripening, 

 it must not be used, but these conditions only occur for a short sea- 

 son, and there is no necessity for using the dust in winter, as then 



