New York AGRICULTURAL EXPERIMENT STATION. 277 
TABLE X.— EFFECTS oF BorpDEAUX MIxTURES MApE WITH VARYING PRro- 
PORTIONS OF COPPER SULPHATE AND LIME, 


FRUIT. 
PLatT Strengthof 








No. mixtures. : 
Injured. senna Injured. | Scabpy. ee Scabby. 
C.S.. Lime Water, Lbs. ozs. | Lbs. ozs. Per ci.| Los ozs.| Lbs. ozs. Per ct. 
5 ae EA ae 1 —1 —50} 94 Sai 2Z050\4..6 4.41 55 10) 2069 4 .6 
AS tt 2 —2 —50} 80 4/1697 5 4.5) 36 6 | 1741 3 -O 
Peet ee 3. —3 —50} 117 — / 1912 4&4 5.7) 38 2; 1991 2 Les 
pO a ae 4 —4 —50! 168 Dette ae lef 12.0" 26 15" |c 1373 -— 1.9 
As Poet ate Check. — — | 1861 13 —| 206 11 1663 2 11.0 
Oe oe 1 —2. —50 34 15 1946 1 VW} £25" -10 1855 6 Gro 
1 Gh ie ae 2 —4 —50| 44 6 | 1881 12 2,0) 174. 14 | 1751 4 9.0 
Soreit.: 3) —6 —50| 193 12 1991 13 8.8] 43 1 ee? 8 1.9 
Ose si 4 —s —50| 86 oh 1184 2 6.7|. 46 8 1224 al 3.6 

These results are in accord with what should be expected 
theoretically, and they certainly are in accord with the experience 
of apple growers throughout the State. Bain*® states the reason 
for the difference in effect between strong and weak bordeaux 
mixtures very clearly as follows: 
“In this connection attention may be called to the difference 
in action between so-called ‘strong’ and ‘weak’ bordeaux mix- . 
tures. One frequently sees in horticultural literature the mixture 
thus referred to, as if the copper were all in solution. The only 
difference between a one per ct. and a two per ct. bordeaux mix- 
ture properly made, so far as their fungicidal action is concerned, 
is that the latter contains twice as much solid copper hydrate as 
the former. From this consideration alone it is clear that a some- 
what larger percentage of the leaf surface will be in actual con- 
tact with copper particles when a certain amount of the stronger 
mixture is applied to a similar leaf surface, than when an equivalent 
amount of the weaker mixture is applied to the same surface. 
Moreover, it is plain that the larger surface of the copper hydrate 
exposed to the solvent action of the water standing on the ‘leaf 
in the case of the strong bordeaux, will produce a saturated solution 
of the copper in less time than would occur in a weaker mixture. 
This latter condition would come into play, probably, more during 
alternating showers and sunshine.” In the same paragraph he 
says: “But from actual experiment the writer has found very 
little difference between the effects of half and full strength 
bordeaux mixtures, and for the reasons here stated it may be 
“Bain (4, p. 95). 
