Smyrna times., 1916-07-12
APPLE BLIGHT EPIDEMIC
AND HOW TO CONTROL It
STATE BOARD OF AGRICULTURE
GIVES ADVICE TO ORCHARDlSTS
Also Recommends Remedy for Canker
Of Pears and Quinces-SYmptoms.
Cause and Origin Related

Frequent outbreaks of this disease
have been recorded from time TO time
since its observation. about 1850. In
Delaware. the disease has been active
for some time; Chester. in 1901. pub
lshed bulletin 50 calling attention to
methods Of distribution and means of
control. Within recent years the
need Of cooperation among orchard
lists in the control of this trouble has
been emphasized.
Symptoms-Blossom blight, fire
blight, twig blight, canker an1 collar
rot, the latter affecting limb and
trunk. are all symptoms Of the same
disease. Twig blight is the most pre-
valent and indicated by the blighting.
burning like, injuries of the twigs
from the tips downwards. Blossom
blight often developes into twig blight
and twig blight may develop into can
kers such as limb and trunk injury.
Bacteria washing down from the twig
and blossom blight often cause collar
rot.
Cause and Origiu-The cause which |
is bacterial was discovered by Burrill |
Of Illinois in 1878. The organism is |
very minute; a million or more may
be carried in a drop Of sap oozing |
from limb or trunk canker affected |
with the disease, or in the nectar of |
single blossom The organism caus-
ing the disease is carried 70 the bios |
SONS and twigs by insects such as flies,
bees, lice and ants. The mouth part |
of a single bee may infect a thousand |
blossoms on one trip.
Now Carried From Season to Sea
son-We have no evidence whatever
that the organism is carried over in
the soil On the other hand. we have
abundant evidence that the disease
carries over in the cankers on limbs
and trunks and that, at the first ascent
of sap in the spring. there oozes out
an insipid gum from such cankers
this gum contains billions of the living
organisms, which may actively cause
disease. This flow of gum takes place
, just prior to blossoming VIXEN nectar
is scarce; the insect in search Of food
, visits these flows, being attracted by
the sweetish odor.
DistributiOn-The nectar loving in
sects having contaminated their mouth
parts from visiting these carry over
n cankers which are actively UoZing,
n will visit the flowers as soon as they
o open. Then begins the wholesale dis
+ tribution Of the disease. resulting in
= the general blossom and later the twig
l. blight so common the present season.
e SCATTERING of the bacterium by rain
: is a secondary means Of spreading the
IS disease. Lice and ants may have
l. much TO do with the late twig infec-
e tion.
ie Conditions Favoring Activity Of
q the Disease-E Excessive rainfall,
moist and saturated atmosphere, heavy
IS dews, and long continued cloudy
r weather are ideal conditions for rapiC
la progress of the disease. Thorough
L cultivation, the use of manure, tn,
81 turning under of heavy leguminOui
IN cover crops. heavy applications q
OF sodium nitrate, in fact any condition
60 or treatment which produces rapid ant
ed sueculent growth of wood will favo
d the development of the disease in III,
&c tissues. On the other hand dryini
e. winds. droughty weather. and eultura
zee treatments which tend to harden IN
wood will retard the spreading of tn
disease.
=H Control-In all severely infecte
districts, control has been possibl
IRA only by the CO operation and activ
MS organisation of the orchardists. Sue
vaI efforts must be backed by strlnger
) laws governing cases Of negligenc,
md Farmer A. with all the skill and know
NOT ledge at his command, cannot contr,
Of the blight in his orchard. il farm,
III. B. across the road. persists in grow
,ed ing infested pears and apples that al
,i,. loaded with gerry over eankers Of q
Of disease. The bees may readily carl
hv the disease several miles. II has be-
t,e shown that the organisms may live
,w- honey for AZ hours.
N. In the face of these facts, it
necessary that all measures must
b,g assisted by a campaign of edueatio
AZ as to the cause. symptoms, means
,ss- which the disease is carried over wi
,ast ter, the manner of distribution, al
fac. method of control Thus far. the mo
,rad successful methods Of control ha
vsr consisted in cutting out the hold ca
rha kers prior to the ascent Of sap in Z
or spring. One days labor in the dc
sets mant season in cutting out such ca
,r,o kers is worth a month of labor
summer. when wholesale infection
.tad rampant. The equipment for cutti
an and disinfeeting consists Of pruni
y shears. (both hand and extension
rom pruning saw, wide ehisel. a mallet,
ak sponge and brush; which is made
and placing one tablet Of corrosive sub