DISEASES OF CULTIVATED PLANTS. 423 
control of rot demands: First, careful removal and destruction of all mummy 
rotted peaches in which the fungus survives; Second, thorough spraying of 
the trees before blossoming, as for leaf-curl; Third, subsequent spray treatmert 
with self-boiled lime-sulfur as per calendar, may be profitable under certain 
conditions. 
Root-Rot. In some instances, notably at Gypsum, Ohio, where peach trees 
were planted in a dense, clay soil, the roots often decay, apparently from the 
attacks of some fungus. Trees thus attacked usually perish soon. Whether 
the trouble is primarily due to the fungus or to the location in which the trees 
are grown has not been determined. 
Se ee 
Fig. 74. Peaches of the Salway variety with one side blackened and cracked from scab. This loss 
is prevented by proper spraying.—From Bulletin 148. : 
Another root-rot has been further studied and found to be prevalent where 
orchards are set in newly cleared land, if following growths of oaks. The 
attack upon the roots show the rhizomorphs of the root-rot fungus as in apple 
root-rot which has later been more often noted in the west. 
Rust. <A rust fungus occurs upon the peach but not to a serious extent 
in Ohio. ; 
Scab or Black-Spot. This fungus (Cladosporium carpophilum Thum.) is a 
serious drawback in the growth of certain varieties which seem susceptible. 
These are Morris, White, Salway and some other late sorts. It causes dark 
spots upon the- fruit followed by cracking and entrance of the rot fungus with 
serious results. To control this disease, spraying results reported in bulletins 
104 and 148 obtained by the use of dilute Bordeaux mixture were very satisfactory, 
but secured with some injury to peach foliage. In 1908-9 studies were made in 
an orchard near Brownhelm where self-boiled lime-sulfur was tested in compar- 
ison with dilute Bordeaux mixture. The results are very promising and indicate 
that self-boiled lime-sulfur is the remedy to be applied at intervals of two to 
three weeks after foliage appears. 
Stem Blight. A stem blight of the peach was studied several years ago by 
the writer. (See bulletin 92). Itis due to a specific fungus which in this. 
instance attacked the stems of nursery stock causing a constriction, and this is 
