EXPERIMENT STATION BULLETINS. 



189 



(he U. S. Department of Agriculture, Bureau of Entomology, in "Insect 

 Life," Vol. VII., pp. 392-5. 



REMEDIES. 



Thrips feed by scraping minute particles off from the soft parts of 

 plants, but as far as their control is concerned, they may be classed with 

 the sucking insects, and we must resort to contact insecticides to kill 



y 



^ie 39.— Onion Ttirips, mature Insect at left, and immature at right, greatly enlarged. (Author's 



illustration.) 



them. Kerosene-emulsion, used at the rate of one part of the emulsion 

 to ten of water will kill them. Tobacco water should also prove effective. 

 Drenchings of cold water are said to be useful when practical, for 

 thrips thrive best in a dry, warm atmosphere. 



Cut-worms (see Insects Affecting Corn). 



INSECTS AFFECTING THE PARSNIP. 



INSECTS AFFECTING THE STEMS AND SEED-CLUSTERS. 



Parsnip Borer {Depressaria heracliana). 



At long intervals, we hear complaints from the growers of parsnip 



seed, of a "worm" that spins webs about the flower-heads, feeding 



therein, and later boring into the hollow stalk. When this insect 



