FLORIDA STATE HORTICULTURAL SOCIETY. 
terially in checking the progress of the 
disease. Burning all old stems and tubers, 
after the harvest, is an excellent practice. 
A systematic rotation of crops is strongly 
recommended. 
Oospora scabies (Thaxter). 
Scab —Attacks only the tubers. The 
skin of the tubers becomes pitted and fre¬ 
quently cracks. These injuries form a 
gateway for an invasion of various fungi 
and insects, which in many cases extend 
the injury. Beets are also attacked by 
this organism. Infected tubers are the 
principal means of spreading this disease. 
When once introduced into a field it re¬ 
mains in the soil for years. 
Treating infested seed with a solution 
of one ounce of corrosive sublimate to 
eight gallons of water for one and one- 
half hours, and one week before planting, 
gives good results, provided the treated 
seed are planted in soil free from the 
organism. A systematic rotation of crops 
gives good results. 
V ermicnlaria. 
Anthracnose —Quite destructive to our 
summer crop. The first account of this 
fungus was given by Dr. Halstead. It 
attacks the stems and may cause pre¬ 
mature death of the plant. Spraying with 
Bordeaux mixture would probably hold 
this disease in check. Burning all of the 
diseased vines as soon as the crop is har¬ 
vested is strongly recommended. 
Bordeaux Mixture —Has proved the 
most efiicient spray for both Early and 
Late Blight, but it is simply a preventive, 
and not a cure for these diseases. It is 
very essential that the spraying be done 
at the right time. If the treatment is de¬ 
layed until signs of damage appear, very 
119 
little good will result. Spraying, to be ef¬ 
fective must be done before any signs of 
disease api>ear, and it must be done 
thoroughly, for unless the entire surface 
of the plant is covered by the mixture 
some of the spores of the fungus will fall 
on the unprotected spots and gain entrance 
to the plants. Frequent applications are 
necessary, especially if sufficient rain falls 
to wash off the mixture. The following 
is the standard formula for Bordeaux 
mixture: 
Copper Sulphate.6 lbs. 
Fresh Lime. 4 lbs. 
Water .. ... 50 gals. 
Potato vines require from 2 to 6 barrels 
of this mixture per acre, according to the 
size of the plants. When spraying is 
done on an extensive scale it is usually 
convenient to make up a stock solution of 
copper sulphate. Suspend a coarse sack 
containing 45 pounds of copper sulphate 
into a barrel containing 45 gallons of 
‘water. The copper sulphate should be plac¬ 
ed near the surface of the water a day or 
two before it is to be used. Stir this solu¬ 
tion thoroughly before using, and one gal¬ 
lon of it will contain one pound of copper 
sulphate. 
A quantity of fresh lime may also be 
slackened and placed In a barrel, and if it 
is covered with a few inches of water it 
can be kept in an excellent condition for 
some time. 
To prepare a mixture from these solu¬ 
tions, take six gallons of copper sulphate 
and place it in the spray barrel, and add 19 
gallons of water. From the slackened 
lime take four pounds of the paste, dilute 
it with 25 gallons of water and add it to the 
copper sulphate solution. All the ma¬ 
terials ought to be passed through a sieve 
so as to exclude the particles which might 
clog the nozzles. 
