38 



into the blossoms of jmipson weeds to poison the moths is worthy 

 of recommendation. It is advised that the late brood of worms which 

 feeds almost exclusively on tomato plants be destroyed by the use of 

 poisons or kerosene emulsion. 



Young tobacco worms 1 were observed on tobacco plants early in 

 July, August, and September. Of these different broods the one 

 appearing in early August is regarded as the most injurious, but the 

 brood appearing in July is not without its bad effects. The station 

 concludes from its experience that the best remedial measure is to 

 spray with a solution of 1 pound of Paris green in 120 to 160 gallons 

 of water, making the application as soon as the young worms appear. 

 The author states that sprajdng more tjian three times is unnecessary 

 when the times of making the application are well chosen. 



In 1896 2 the tobacco worm was very abundant, and further observa- 

 tions were made by the station entomologist. The average persistence 

 after treatment of the young worms was 4.13 days and of the large 

 worms 12.33 days. The average duration of all lots of worms treated 

 with a solution of 1 pound of Paris green in 10 gallons of water was 

 four days, and when a mixture of 1 pound of Paris green in 150 gallons 

 of water was used, 11.17 days. The weaker solutions were found 

 sufficiently strong for the destruction of the young worms, but in des- 

 troying the large worms the strong solution proved the most effective. 



The Maryland Station 3 found that a poisoned mash, consisting of 50 

 pounds of wheat bran, 2 quarts of molasses, 1 pound of paris green 

 and water, dropped from three to five days before planting, near the 

 places where the plants are to be set, prevented the cutworms from 

 injuring tobacco fields. 



In testing tobacco seed the Florida Station found that apparent 

 damping-off of the seedlings was due to nematode attacks/ The seed- 

 lings were grown in sand which had been kept air dry for ten months 

 prior to sowing the seed. The injury was produced by the Avorms 

 from the outside at any point on the plant. When attacked the points 

 of irritation became enlarged, the development of the seedling was 

 arrested, and the final result was the destruction of the young plant. 

 To prevent the trouble, the author advised growing tobacco seed on 

 uninfested soils, and states that old land is apt to be infested, and that 

 this may be ascertained only by observation of the trouble in pre- 

 viously grown crops. 



TOBACCO AS AN INSECTICIDE. 



As an insecticide tobacco has a wide application and its use for this 

 purpose, it is safe to say, has been tested by every experiment station 



1 Kentucky Station Bui. No. 63. 3 Maryland Station Bui. No. 55. 



2 Ibid. No. 66. 4 Florida Station Bui. No. 24. 



