12 



FARMERS BULLETIN 



Fig. 14. — Bean leafhopper, an 

 insect which is also injarious 

 topotato: At right, adult insect; 

 at left, wing extended , showing 

 venation. Much enlarged; 



injury was to potatoes, followed by toma- 

 toes, cabbages, and many other food plants. 

 In most cases it caused the greatest consterna- 

 tion and fear of losses, especially among 

 o\\'ners of small gardens, who were absolutely 

 unacquainted with the insect and the remedies 

 to apply for it. 



Leaflioppers and plant-hce do not feed 

 upon leaf tissue, but insert their beaks into 

 tlie tissue and drain the vital juices of the 

 plants, thus weakening them so that a great 

 reduction in the yield ot potatoes results. 



SPRAYS FOR LEAFHOPPERS AND PLANT-UCE ON POTATO. 



Nicotine sulphate, a contact insecticide, has been used experi- 

 mentally as a spray against the bean leafhopper and the potato aphis 

 on potato, and its use has been attended with some success. The 

 stanrlard formula is as follows: 



Nicotine sulphate, 40 per cent solution pint . . ^ 



Fish-oil or other soap, dissolved pounds . . 2 



Water gallons . . 50 



Everything considered, nicotine sulphale is for several reasons 

 preferable to kerosene emulsion or soap solutions, is more easily pre- 

 pared, and is manufactured as a standard solution, containing 40 per 

 cent, by weight, of nicotine. Usually it is used at a dilution of 1 part 

 of 40 per cent solution to 1,000 parts .of water. For a "spreader," 

 or ''sticker," about an equal quantity (see formula), or a little more, 

 of soap is added to the entu'e solution. Common yellow bar soap is 

 perfectly satisfactory for ordinary purposes. For thoroughness this 

 solution should be applied in as fine a spray as possible. Most insects 

 are reached more readily by a fine mist, but for sucking insects the 

 spray should be applied at considerable pressure so that every insect 

 is actually reached or hit by it. 



For use in small gardens, 1 teaspoonful of nicotine sulphate is used 

 in 1 gallon of water, and t.> this a 1-inch cube of hard soap is added 

 and the whole thorougldy mixed. If a larger quantity is needed, 

 1 fluid ounce of nicotine sulphate, 8 gallons of water, and one-half 

 pomid of soap aro us.hI. Directions arc furnished on the* covers of 

 packages, and frequently mstructions accompany them. 



Kerosene emulsion, apphcd as for other sucking insects, is valuable 

 also but is being superseded by nicotine sulphate solutions.^ 



For loafh()pi)crs alone, as they occur on potato, bean, and other 

 plants, still another remedy is "Used, a capturing device called a 



1 Directions for the appHcatioi of kerosene emulsion will bo furnished by the Bureau of Entomology, 

 U, S. Department of Agriculture. 



