20 MISSOURI BOTANICAL GARDEN BULLETIN 
fungi. The fungicides used are potassium sulphide (1 
ounce to 2 gallons of water) ; Bordeaux mixture (5 pounds 
copper sulphate, 5 pounds lime, 50 gallons water) ; ammo- 
niacal copper carbonate (6 ounces copper carbonate, 3 
pints ammonia, and 50 gallons water); and flowers of 
sulphur. 
Killing of fungi hibernating on bark of dormant plants. 
—The sprays for this purpose may be of greater toxicity 
because of the dormancy of the plants. They are copper 
sulphate with just sufficient lime to color, and lime-sulphur 
mixtures, 
The use of protective sprays.—Protective sprays are those 
which are applied to the plant to kill any organism which 
may fall upon its surface. Bordeaux mixture and ammo- 
niacal copper carbonate are the fungicides most commonly 
used, and, as they are employed when the plants are in 
foliage, must be of weaker solution than those used for dor- 
mant plants. To be effective the spray must be applied 
about once every two weeks in order to replace that washed 
off by rain and to protect the newly appearing surfaces of 
leaf, twig, or fruit. 
The most common types of sprayers are the bucket pumps 
suitable for use in a garden; the compressed-air sprayers, 
which are partly filled with the spray mixture, then closed 
and air pumped in, exerting pressure upon the liquid and 
forcing it out in the form of a fine spray; the dusters which 
consist of various forms of bellows or blowers operated by 
hand, discharging sulphur evenly and economically. 
The following table indicates the more common diseases 
that are eradicated by spraying: 
ComMoN NAME TREATMENT FREQUENCY 
Apple saab... ccs -- Bordeaux mixture...... 3-4 times in summer 
Asparagus rust....... BUI QNUE oso sas Se 
Carnation rust........ Copper sulphate (1 Ib. to 
25 Ser ee 
Celery leaf-spot.... Bordeaux mixture...... 
rysanthemum mildew Sulphur ............... 
Chrysanthemum rust.. Bordeaux mixture...... 5-6 times 
Chrysanthemum spot... Bordeaux mixture...... 
Cucumber powdery mil- 
chad PER TENE Le PRITAM gs cea cass: 
Currant anthracnose... Bordeaux mixture...... 5 times 
Currant leaf-spot...... Bordeaux mixture...... 5 times 
Cyclamen spot........ Bordeaux mixture...... 
Dahlia powdery mildew Sulphur ............... 
Fern blight... .25. 2... Bordeaux mixture...... 
Grape powdery mildew. Bordeaux mixture...... 5-6 times 
Grape rot. oss chk Bordeaux mixture...... 5 times 
