DISEASES OF CULTIVATED PLANTS 373 
liable to be rendered unsightly and unsalable by the spots which are illus- 
trated in Fig. 32. In seasons like that of 1909 the disease may appear on 
unsprayed trees in practically all situations. It was found in comparative 
tests of Bordeaux mixtures and self-boiled lime-sulfur for apple scab and other 
fungi, at the Carpenter test farm, that the sooty fungus appeared on the fruit on 
the lime-sulfur trees. It is 
thought by several that this 
fungus spreads upon the fruit 
after itis stored and at whatever 
time it appears it renders apples 
dull, unsightly and ‘unsalable. 
Bordeaux mixture or its modifi- 
cations may be relied upon to 
hold the fungus in check. One 
spraying at the time the apples 
are the size ot hickory nuts may 
prevent nearly all of the injury. 
Upon varieties like Maiden’s 
‘Blush, Grimes and Belmont the 
spraying should be done a little 
earlier than just stated. The 
demonstrations by the Station 
all over the state, show clearly 
what improvement the spraying 
makes in the apples where this 
trouble prevails. 
Sun-Scald, Collar-Rot. There 
is frequent complaint of the 
dying of the trunk of both young- 
er and older apple trees wherein 
there appears to be associated 
the exposure to sun and the 
death of the bark of the. trunk 
upon younger orchard trees. 
The freezing injury has been 
carefully worked out in recent 
years and is discussed under 
be 
winter injuries, with several Bee ei ee 
varieties of apples, notably the : 
Grimes and King this trouble Fig. 32. Apples spotted by sooty fungus. The apples 
is so serious over much of Ohio shown above were sprayed with Bordeaux mixture fol- 
lowed by two sprays of Bordeaux and Iron Sticker. The 
as to reduce the growth of these apples shown below were sprayed first with Bordeaux 
sorts; while Murrill has sug- mixture and this was followed by two sprays.of self- 
gested a connection between a boiled lime-sulfur. In neither case was the scab entirely 
fleshy fungus and this dying of prevented. Thelime-sulfur spray was not strong enough 
the trunks of the King thé Gon to keep offlate attacks of sooty fungus. From a photo- 
graph by T. F. Manns. 
nection has not been proved. The 
injuries which occur on the south and southwest exposures of the trunk have 
probably a direct connection with the danger from freezing injuries. Some 
apparent sun-scald is.more probably due to the bacterium of pear blight as has 
been recently proved by cultures from young trees by Waite. With Grimes 
and other varieties susceptible to collar-rot caused by the bacterium ot 
pear blight the only true relief is found by top working on some vigorous 
sort such as Baldwin, Gano, and like varieties. ‘In the case of true 
