THE GRANVILLE TOBACCO WILT. os 
organism is not known to produce spores and is believed to be de- 
stroyed by a short exposure (ten minutes) to 52° C. (125° F.), but 
until it has been confirmed on a large scale in the field it is best to 
be cautious about using waste material from the curing house. Some 
portion of it containing these bacteria may not have been heated hot 
enough to destroy them. 
(11) Strive to keep uninfected fields free from infection. To this 
end look out for the tobacco refuse; also for wash of rain water from 
infected lands (this to be turned aside by ditches and dikes). Be 
watchful also for other sources of infection, e. g., dirt or fragments of 
infected tobacco carried on tools, feet of horses and cattle, ete. 
Tools may be disinfected (after removing the dirt) by a short expo- 
sure to live steam, boiling water, or the open flame (gasoline torch). 
Five minutes’ exposure ought to be ample. They may also be disin- 
fected by the use of germicides, e. g., 5 per cent carbolic acid (poison) 
or one-fifth per cent mercuric chlorid (poison). Carbolic acid or mer- 
curic chlorid (corrosive sublimate) are better than formalin, since the 
latter is volatile and likely to be under the certified strength (40 per 
cent formaldehyde) in broken packages or old corked bottles. Mer- 
curic chlorid tablets prepared for this purpose, so that weighing is not 
necessary, are on the market. Wooden pails and clean boiled water 
should be used. The germicidal action of mercuric chlorid is destroyed 
by contact with metal dishes. These substances should be kept out of 
reach of children. 
(12) Avoid also the increasingly common southern practice of sowing 
fields with dirt from other fields, the idea being to inoculate the soil 
with nitrogen-fixing organisms. This method of inoculating soils isa 
bad practice under any circumstances, 1. e., one well calculated to dis- 
seminate plant parasites and one particularly reprehensible in localities 
where this disease prevails or is liable to occur. Nematodes, injurious 
insects, parasitic fungi, club-root of cabbage and other crucifers, and 
plant-destroying bacteria, not to mention animal parasites, are all 
liable to be disseminated in this way. To let loose a whole menagerie 
for the sake of obtaining an ox or an ass is not a good policy. Obtain 
pure cultures for soil inoculations from the Department of Agriculture 
or the State agricultural experiment station. 
(13) Those who grow Sumatra wrapper-leaf tobacco under tents 
erected at great expense, and whose annual crop is worth $1,000 or 
- $1,500 per acre, can afford greater expenditures in combating this dis- 
ease than the ordinary planter. Such persons should endeavor to free 
the soil of this organism by fire or by steam heat. They should also 
combat the nematodes. Bacterium solanacearum is quite sensitive to 
heat, and if the whole body of the soil could be warmed up to 125° F. 
for fifteen minutes this organism would be destroyed. If such attempts 
fifteen minutes this organism would be destroyed. If such attempts 
are made great care must be taken that the sterilized portions are not 
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