Martinsburg statesman-democrat. [volume] (Martinsburg, W. Va.) 1906-1921, 1912-06-21
CEDAR RUST ON APPLE
AND HOW TO AVOID 1T
Maryland Man Has Been Expert
menting and Gives Some Very
Valuable Advice.

~hR wv
/ have been experimenting with
cedar rust ia my orchard. 1 had sew.
eral cedar trees growing among m,
apple trees. Trees not properly treat.
ed win suffer badly from this dis.
ease. There occur on The fruit and
foliage OF the apple. orange colored
spots. which cause considerable dam.
age TO certain varieties On practically
all apple growing districts Of thu
Eastern United States The disease
is known as cedar rust, because The
fungus responsible for the trouble
passes one stage of los existence on
the apple. ounce and other poma.
cious plants. and there are two or
three different species of rust fungi
involved. but the one named above
seems to be the chief cause Of the
disease on the apple. Infections can
take place only from spores produced
on the cedar trees, aud the disease Ia
therefore confined TO localities where
this plant grows. The cedar RUS,
disease manifests itself on the leaves
as minute pale yellow spots. which
slowly enlarge, finally attaining ono.
eigth to onefourth inch In diameter.
with age they become orange-coluret,
with small, black dots In the center.
and on the under surface of the leaf
beneath each spot the tissues be.
comes swollen. forming blister or
cushion on which eup-shaped sporr
reaeptacles are produced, These re-
ceptacles are small tubular proiac.
lions with fringed margins susoep.
tlble varieties adjacent to cedar trees
may become so badly affected that
the trees appear yellowish and later
become partially, IL not totally, de.
follated, Even though the diseased
leaves may not drop. their functions
are 80 interfered with that the fruit,
the buds for the following year and
the tree itself ia not properly nourish,
Ell. This results in weakening of
the tree and the production of small,
immature, pooriy-colored fruit and
weak buds, On the fruit of the apple
the disease appears as bright yellow
or sometimes greentahYellow spots
about onehalf inch In diameter or
larger On the Smokehouse, for ey.
ample. blossom end infections are the
rule. while on the Ben Davis the apots
occur more commonly ia the side OF
the fruit The disease extends well
into the flesh sometimes reaching tho
core, and the affected fruit may be-.
come deformed or atrophied "A a
rule. however. there IL no disfgura.
ton other than the presence of the
yellow spot and the ronghness Of the
skin over the GiseaFed area, much az
1t being UNFIT for market. The dia
ease on the fruit Ia NOT SO import mt
as that on the foliage. the greater
damage being caused By the latter
Tho Infections OF the cedar with
spores from the apple take place dur
ing July, August and September, thr
fungusfungus begins to grow IN the
tissues of tho cedar branches, and
there passes the winter IL starts
growth the following spring, and by
fall the cedar apples have reached
full growth In wet weather, during
the second spring after the Infections
On the cedar take place. the fungus
In these gals throws out long. gela.
tinous projections In which compare
lively large spores are borne, While
still In the mass, these spores germin.
ate producing a short fungous growth
which bears crop Of smaller second.
airy spores, Upon drying these second.
airy spores are carried like dust par.
ticles on the wind. and when lodged
on the fruit or foliage of the apple
terminate Beginning about the time
apple trees are In bloom. infections Of
.he fruit and foliage of the apple may
take place ever a period Of three TO
six weeks, depending upon weather
conditions. I'm wet weather during
this period, the cedar apples throw
out the yellow masses and these may
dry out and swell up again several
times with alternate dry and wet
weather. more spores being liberated
each time Moisture is not only nee
essary for the production OF the
spores from the cedar. but for their
termination ON the fruit and foliage
OF the apple. Intermittent wet wealth
er may therefore prolong the infee-
ton period and result in serious out
break of the disease. Spraying for
the control Of this disease has not al
ways proved successful and many
growers have been disappointed In
the result have perfected a line of
treatment that will positively cure
this disease and all other diseases OF
fruit trees that ! will give to the pub
lie In the near future.
c. MICHAEL FISCHER, M. %.
Big Pool, Md.