SUGGESTIONS TO GROWERS FOR TREATMENT OF TOBACCO BLUE- 

 MOLD DISEASE IN THE GEORGIA-FLORIDA DISTRICT. 



THIS CIRCULAK has been issued with two ends in view (1) the 

 saving of as much as possible of this year's crop and (2) the 

 protection of future crops. The sudden appearance of a tobacco 

 Peronospora in five widely separated seed beds at approximately the 

 same time and its rapid spread to almost or quite all the other beds, 

 together with its discovery on a weed in one seed bed and its subse- 

 quent appearance on tobacco in the field, both under shade and in 

 the open, even when set with supposedly healthy plants, along with 

 the well-known destructive character of all parasites of this group 

 (downy mildew of the grape, downy mildew of the cucumber, late- 

 blight of the potato, tobacco Phytophthora, etc.) makes it plain that 

 a very dangerous enemy has been introduced and that it can be con- 

 trolled only by a concerted effort on the part of all the tobacco 

 growers of the Gadsden-Decatur district along intelligent and well- 

 directed lines of disinfection, protective spraying, and field sanita- 

 tion, as outlined below. 



THE SEED BEDS. 



The tobacco seed beds should be cleaned up at once. All trash 

 (weeds, dead tobacco plants, etc.) should be burned. The beds 

 should then be soaked in a solution of formaldehyde, using 1 part 

 of the commercial 40 per cent formaldehyde (formalin) to 100 

 parts of water; or, in place of this the bed may be sterilized by the 

 inverted steam-pan method for 30 minutes. However, when steam is 

 used it will be necessary to treat the ground around the posts and 

 around the edges of the field with the above-mentioned 1-to-lOO 

 formaldehyde solution. The posts, and the walls when they are of 

 wood, should also be thoroughly sprayed with the formaldehyde 

 solution. The cheesecloth used to cover the seed-bed should be 

 burned or thoroughly boiled or steamed. Formaldehyde solution is 

 not recommended as a disinfectant of cheesecloth, because of its 

 tendency to make the cloth hard and brittle and therefore useless. 



These beds should be resteamed or burned, as is usual preceding 

 the seeding. Care must be used in handling the formaldehyde solu- 

 tion. This does no injury to the land, as it is readily decomposed in 

 the soil and what is not decomposed rapidly evaporates, leaving the 

 land sweet. However, it will harden the skin and make it crack and 

 will cause smarting of the ej^es and nose if carelessly used. Those 

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