Forcing Tomatoes. 



261 



Various trials made — Fumigations made in full daylight, using 

 two, three and four ounces of cyanide to each one thousand cubic 

 feet of space for twenty minutes, the temperature of the house ranging 

 from seventy to eighty degrees, resulted in slight injury to the foliage 

 of tomatoes and severe injury to the foliage of chrysanthemums, 

 geraniums and begonias. 



Two ounces of cyanide for two hours, house at sixty-five degrees, 

 but damp; exposure made at six p. m.; injury to chrysanthemums 



Fig. 11. — Lester s Prolific tomato, an excellent winter variety. 



not serious. Under these conditions and using the same amount 

 resulted in quite serious injury to tomatoes. 



Two ounces cyanide, temperature sixty degrees, with dry atmos- 

 phere and all-night exposure resulted in very slight injury to cucum- 

 ber vines and the destruction of over ninety per cent of the insects 

 (white fly). One ounce cyanide, house dry, sixty degrees or below, 

 dark, no injury at any fumigation. Insects mostly killed. 



