21 
dred, those of the second 258, and those of the third 189. The average weight of the 
fruits in the different qualities appears below in Fig. 2. 
C 
Fig. 2.— a, first quality; &, second quality; c, third quality. 
Had all the fruits from the eighteen Fameuse trees been equal in size to those of 
the first quality the actual increase of the crop would have been a trifle over 413 
pounds, or more than 17.8 per cent of the entire yield of apples. This, it should be 
remembered, only represents the effect of the scab in reducing the size of the fruits 
actually developed. It does not take into account the injury to the appearance of 
these fruits, the fruits that were prevented from developing, nor the injury wrought 
by the fungus to the vigor of the tree. 
Cost of the treatments .—From the materials and the time consumed in the treat¬ 
ments, counting copper carbonate at 50 cents per pound, ammonia $1.50 per gallon, 
and labor 15 cents per hour, I have computed the cost of the treatments with these 
materials approximately as follows: 
Cost for spraying one tree once with ammoniacal copper carbonate: 
For materials...$.022 
For labor.0375 
Total. .0595 
Or, including labor of preparing, about 6 cents. 
Suspended copper carbonate, using double the amount as in the above: 
For materials.„. $.0039 
For labor.0375 
Total.0414 
Or, including labor of preparing, about 4.2 cents. 
These prices could be considerably reduced by purchasing the materials in quantity 
and making the applications with a larger force pump. 
I have not been informed as to the cost of the sulphur powder or Mixture No. 5.* 
Eecapitulation .—The results of the experiment in the treatment of apple scab, 
described in the foregoing pages, suggest the following conclusions: 
I. That in seasons of excessive rains in early summer the scab on badly infested 
trees can not be wholly prevented by the treatments given in this experiment. 
II. That of the substances tested the mixture of ammonium carbonate aud ammo- 
niated copper sulphate (designated as Mixture No. 5)t was most efficient. 
III. That the precipitated copper carbonate applied stirred in water, as we use 
Paris green, is nearly or quite as efficient as when one-half the amount was applied 
dissolved in ammonia, a point which, if confirmed by further trials, is important, as 
it will render possible the use of Paris green for the codling moth at the same spray¬ 
ing with the fungicide. 
IV. That early treatments, and especially at least one treatment previous to the 
opening of the flowers, is extremely important. 
* I mention, on the authority of Dr. S. M. Babcock, that this material is, when 
dissolved in water, very similar in chemical composition to the ammoniacal copper 
carbonate. On adding water to the mixture a chemical change takes place, the result 
of which is the formation of copper carbonate dissolved in ammonia aud ammonium 
sulphate. 
t Mixture No. 5 costs practically the same as the ammoniacal solution. 
