APPLE DISEASES 
the circulation of sap and the food sub- 
stances. This lack of circulation and lack 
of air, is caused by the packing or run- 
ning together of the soil particles in irri- 
gation, forming a tough, waxy substance 
through which water does not penetrate, 
nor the air circulate.” 
Some of the letters and bulletins from 
which these extracts were taken are near- 
ly two years old, and may not fully rep- 
resent the views of the writers and auth- 
ors at the present time, but I have seen 
nothing from their pens to the contrary, 
and believing that they express truth, I 
have quoted from them in support of my 
own Views. 
“Rosette occurs in the pecan and the 
following note as to its cause and distri- 
pution from M. B. Waite, of the Depart- 
ment of Agriculture, is appended. 
“The pecan rosette occurs in humid re- 
gions. I have seen it most abundantly in 
South Carolina, Florida and Alabama. I 
am under the impression also that it oc- 
curs in Texas, but have not any definite 
reports by which I can give you its dis- 
tribution in that state positively. The 
points in which I have observed it in 
South Carolina, Florida, Georgia and Ala- 
bama are not only in the humid Eastern 
states, but in distinctly moist sections 
near the Atlantic seaboard and the Gulf 
coast. The pecan grows with great lux- 
uriance in the bottom lands along the 
Mississippi and its tributaries in Louis- 
liana, but I do not recall having seen the 
rosette on these bottom land trees. I 
have not, however, personally hunted for 
the disease in this section. 
“Doubtless you know that the pecan 
rosette is a little known disease. It is 
under investigation by the Department 
and is supposed to be a physiological 
trouble induced by soil conditions. We 
are not prepared, however, to say just 
what these conditions are. 
“Now, as to the apple rosette, it does 
occur rarely in the Eastern states. It 
has occurred at Winchester, Va., during 
the years 1911 and 1912, on a few trees of 
York Imperial in a young apple orchard 
five or six years old and just beginning to 
bear some fruit. It was also found in 
485 
1911 in Loudoun county, Va, east of the 
Blue Ridge and some 30 miles distant 
from Winchester. It is a notable fact, 
however, that this rosette should appear 
after two or three very dry seasons. In 
the district named, the latter part of the 
season of 1909 and the seasons of 1910 and 
1911 were notably dry, particularly the 
summers. Springs and wells, as well as 
streams, were lower than they had been 
for many years. Fairly good crops were 
produced, except the hay crop of 1911, due 
to drought in June, but there is no doubt 
about the general deficiency of subsoil 
moisture during this period. 
“It should be stated that apple rosette 
is so rare in the East as to be only of 
scientific interest It is not abundant 
enough to be of any serious economic im- 
portance east of Nebraska and Kansas. 
From those states westward it is one of 
the most important orchard diseases. The 
disease called Chlorosis, which we have 
considered to be somewhat related to ro- 
sette and which intergrades with it in the 
West, behaves in the same way. This 
physiological trouble is an important dis- 
ease from the Missouri river westward, 
but is rather scarce all over the humid 
states. It occurs, however, much more 
frequently than the rosette, and I have 
observed it in several states, notably New 
York, Pennsylvania, Maryland, West Vir- 
ginia and Virginia.” 
GRANVILLE LOWTHER 
Rust 
Gymnosporangium spp. 
Apple rust is a widely distributed dis- 
ease, and in some sections is quite in- 
jurious. It is of common occurrence in 
Eastern states and, while not one of the 
most serious apple troubles, it often does 
considerable damage. It sometimes at- 
tacks the fruit, but its effects are usually 
confined to the foliage. Here it causes 
yellowish spots which usually become 
somewhat elevated in the center and in 
which are produced numerous spores. The 
spots usually appear on the leaves in 
June. The spores from these spots are 
borne by the wind and attack the twigs 
of Junipers, causing morbid growths or 
swellings. One of the most characteristic 
