DISEASES OF CULTIVATED PLANTS 359 
SOLUBLE COPPER COMPOUNDS AS SPRAYS 
Whenever it becomes necessary to continue spraying upon 
fruit as ripening approachesa more soluble copper compound than 
Bordeaux mixture must be employed or the spray will remain upon 
the fruit at marketing. The remaining spray, if excessive, injures 
the marketable character of the crop. Various sprays have been 
proposed for use at these critical times. The call for them has 
come in keeping down the black-rot on the grape and in the control 
of the several late season diseases of fruit, like the bitter-rot and 
black-rot of apple. The most satisfactory soluble copper sprays 
appear to be ammoniacal solution of copper carbonate or Soda Bor- 
deaux mixture. ; 
For the former the following formula is given: 
AMMONIACAL SOLUTION OF COPPER CARBONATE 
Copper’ Carbon ate rwrassiesinessuneesnassasssewimsersnnannye 6 ounces. 
AMMONIA) csyceanwesniuyiven cexeeveondaanandemeeecs wens about 3 pints. 
(Enough to dissolve the copper carbonate and no more). 
Water to make... cece eccce renee ena eeenane 50 gallons. 
This isan effective spray made according to formula for the 
late applications upon grape and upon appleas maturity approaches. 
Itis to be understood that this formula is not intended to make 
“eauceleste’”’ which is a different preparation. No more than enough 
ammonia is added to convert the copper carbonate from insoluble to 
soluble form in the presence of water. A soluble salt of ammonia 
and copper is really produced. ‘The proper times at which to make 
applications of fungicide as sprays has been carefully worked out in 
practice and directions are included in the spray calendars. There 
isa good reason in nearly every case for making the applications at 
the time recommended, since these sprays are timed to check the 
development of the parasite; if put on too long in advance the spray 
may be displaced, if put on too late the damage will occur without a 
possible means of prevention. All sprays as stated before are made 
in anticipation or in advance of actual danger from parasitic diseases. 
SULFUR COMPOUNDS AS FUNGICIDES 
Various preparations of the sulfids of alkalis and alkaline earths 
have been proposed as fungicides. A larger use has been made of 
the lime-sulfut formulae which have come into use largely for check- 
ing scale insects. These mixtures are made by boiling together caustic 
lime and flowers of sulfur in the presence of water. By this heating 
process a combination is effected between the calcium and the sulfur, 
and sulfids of various compositions are formed. For practical 
purposes the color reactions are used as a guide. This spray applied 
