76 Nebraska Agricultural Exp. Station, Research Bui. 10 
Grit or hard materials of any kind in the solution may cause 
russeting by being thrown against the surface of the fruit with 
considerable force, thus destroying the waxy covering of the cells 
or the cells themselves and allowing them to be more easily injured 
by the corrosive action of the spray. 
It is the opinion of the writer that a great deal of the so-called 
spray injury to the leaves is due to infection by fungous diseases. 
It was noticed that either Bordeaux and lime sulphur injury was 
as a rule more conspicuous in the orchards where there was an 
infection of blotch. This was also true of lime sulphur in 1915 in 
the orchards where the scab infection was most severe. The spray 
when applied where infection has occurred finds a ready entrance 
into the leaves at the infected parts and consequently destroys 
the contents of the surrounding cells, causing the well-known 
spotting. This has also been noted consistently in other orchards, 
the spray injury in the form of spotting of the leaves occurring more 
abundantly in orchards infected with blotch or scab and appearing 
in greater numbers after the last spray of the summer. 
Hedrick (1907) states that the scab fungus often causes a russet 
closely resembling spray injury to appear on apples and pears. He 
also mentions the resemblance of Bordeaux injury on the foliage 
to the injury caused by species of Phyllosticta. Stewart and 
Eustace (1902) found that the spots caused by Bordeaux injury 
were free from the pycnidia or Phyllosticta in early summer, 
July 10, but that later the majority of the spots contained a 
species of Phyllosticta, but they raise the question as to whether the 
fungus does not appear as a saprophyte after the Bordeaux has 
caused the injury. 
As a rule, even where russeting is negligible, fruit sprayed with 
Bordeaux is not so bright colored and attractive as fruit sprayed 
with lime sulphur. Tiny gray flecks are scattered over the surface, 
marring the otherwise smooth, waxy appearance. This condition, 
however, is not so noticeable where Bordeaux is used during the 
latter part of the season and is not followed by rain. 
SUMMARY 
The results of the three years' work with Bordeaux and lime 
sulphur indicate that Bordeaux is very little if any more effective 
than lime sulphur as a fungicide under Nebraska conditions, ex- 
cept in the control of apple blotch. 
The danger of injuring the fruit which accompanies the use of 
Bordeaux makes its use inadvisable except where serious infections 
of blotch occur. 
(1907) Hedrick, U. P. Bordeaxxx injury. New York (Geneva) Exp. Sta. Bui. 287:139. 
(1902) Stewart, F. C, and Eustace, H. J. Two unusual troubles of apple foliage. (Pt. n) 
New York Sta. Bui. 220:225-233. 
