The Parma herald. (Parma, Idaho) 1903-1917, 1910-06-09
FIRE BLIGHT in APPLE TREES
A Brief Description o. the Disease
ard Its Cure.

Corvallis.
, Fire blight is the most serious Of all
the diseases which attack the pear and
apple. 1t is contagious disease of
bacterial origin which, under proper
conditions, may attack any part Of the
tree Besides the pear and apple, the
ounce, wild crab apple, hawthorns,
mountain ash, serviceberry and some
other pomaceous trees are subject to
attacks Of this disease.
Myriads of germs are present in all
freshly blighted portions of the tree
and in the sticky ooze exuding from
cankers. The germs live almost en-
tIrely in the sappy portion of the bark,
though in some vigorous growing vari-
cites Of pears the germs have been
known to invade the sap wood to a
limited extent. Fire blight occurs in
more or less severity in nearly all
parts OF the United States where
pears and apples are grown.
In Oregon fire blight mas appeared
in two general localities - one in the
Southwestern part Of the state, includ
ing the Rogue River valley, the other
IN the Northeastern part.
Beginning in the spring the first ap-
parent damage produced by the disease
In an infected orchard is the blipbtino
OF the blossoms. Infection is brought |
ABOUT by insects, principally bees,
wnicn have visited case of hold-over
blight and become covered with the
organisms contained in the sticky ex-
udation, inoculating the flowers in
their search for nectar. The organ
isms divide and multiply in the nectar
and are able to enter the living tissues
through the unprotected hectares.
Having entered the tissues they quick
" blight the blossoms, pass down the Q
and into the fruit SPUR.
Siiiing the tissues and cutting off the C
caves from water supply, causing t
hem to shrivel and dry, thus produce a
ng fruit spur blight" The latter t,
occurs several weeks after. blossom in a.
ectlon- In very serious cases nearly
u the fruit spurs may be blighted in fl
MS way and the trees set no fruit W
Usually the germs die out and do not SC
row into the twig or branch on which SO
ne spur occurs, but occasionally the M
erms may continue into the bark of l(
1e branch at the base of the fruit spur at
nd form typical canker. Fruit spurs TO
the larger branches are a fruitful
'urce of body infection and MANY ne
uses OF blight canker originate in ia
is way. Al,
The name fire blight is given to wi
is dioease because of the characteris-
appearance of pear foliage on twigs no.
branches which have been killed bv col
e organisms. The leaves turn black tbs
though scorched by fire and fire. wa
emily remain on the tree during the ,
lowing winter. 1t should be noted ed
&c this color of the foliage is charac- wa
'istic of the pear when it has been ton
led during the growing season. If {
'wer not familiar with the pear tina
gnt desires to known how the "twig of
gnu looks let him girdle a twip in offe
1,summer and watch the results. bet
ne cankers are also quite character Diet,
9 put are very variable in appear late
e.. The disease progresses most
ioiy In the fieshy outer layer of the A
and at first produces q wateyv
earsnce in the affected area. Later
tissues OF the bark are more or less ''''s
zen down and the cankers become
< in color. :.
N
esldes the blight cankers found on est ,
limbs and trunks, one frequently nour
IN some varieties of pears and who
zenberg apples a larger canker Of test
surface of the ground extend;r,r carr,
ne trunk for some distance and ped
n the large roots. This cord;t;os. park
lied collar rot. and NOV ,as,,14 the {
| blight canker will
pear tree wbon h.5, fits G
y recognized at distance in the ees'
to the foliage ee' al feuoisn the '
ene apple the foliage of twig and
spur blight turns brown and drv Al
e OF the most fruitful sources of w
tion has been by the pruning nay e
3 or saw. In pruning. if an Sos
canker is cut into, the tools he 'ne
injected and serve as inoculatino a'ine
lments to spread the disease. passs
only method known of control Dee"
nre blight is to cut out all cases cue Il
yinp with fnro;a;aa aPpear.- road
ementarv v.l,,a -, =, u oniy from
cures are worse than useless. NnoA
permanent valne 20 at. ~ - % ing fl
Ut the fruit spur and twig blight
icy appear. Unless these forms
oisease extend into the branches Pit
llch they occur and a cankar IL the u
"a the disease USUALLY bacor,os drive
any limited and the germs pradn- busint
ie- try h
efforts of the grower should be sidiar,
.eu 70 cutting out all cases of are v
:, canker and body canker during pender
VI, winter and early spring. when houses
mixers nave become more or less in Pitt
q IN Their growth and are NOT pleted
ly spreading. "o' jobber,
inner cutting is intelligently an compal
Is frequently of great value laugh
uiarly where there is only a l;ttIs
o., IN the autumn before the
ran is good time to do the cut Portl
. sh an cases OF twig blight are apparel
$50 sSu- mother
=. should De particularly ex- zling
- eases OF the collar rot. II showing
iorin Oh the disease that causes with D
.lees 70 be killed outright when Il
,tting out cankers it is necos than a :
nat the tools be kent n,o;st interest
, ,o good disinfectant.. If this belied b
me- eaen cut will reinoculate to view