The Columbia herald. [volume] (Columbia, Tenn.) 1850-1873, 1871-09-01

This disease has become 30 destructive OF
late years, particularly In Pear culture - to
deter many Orchardists nom the cultivation OF
this fine fruit.
extensive country, il was wholly unknown,
WHY has it become so destructive Of late years
There is q natural cause for its almost univer-
sal appearances: Nearly all Horticulturists
have their theories to account for its causes,
differing very widely in their conclusions.
For IL years, have studied it very attentive
ly in the orchard, as to cause, preventive. and
remedy, and will here state, that have so far
succeeded as not to fear it in planting extcn-
sive pear orchards.
We do not find Blight every year, but only
occasionly, and only then OF one season of the
year, about themonth Of May.
Those varieties of rapid, upright growth, are
the most seriously affected, while the leaves
and twigs are in a succulent, tender and rapid
growth. The slow growers, and those Of
spreading and horizontal growth, are only sub.
ject to the disease by injudicious culture and
pruning.
This disease is always preceded by the like
climatic influences, heavy cold rains, and much
bright warm days, while the trst spring
growth is in q very tender, watery, and imma-
ture state.
The idea Is not satisfactory that Il is caused
BY the sudden freezing of the sap and tender
growth at The close of the previous season.
For, we find, that growth in the Fig is effectu-
ally killed, and never puts forth leaves in the
spring.
1t has been largely attributed to the myriAds
of insects. This is not at all satisfactory.
They Should as well attack the Seckel, . slow
grower, as the Madeleine, of erect, rapid
growth, and then every year alike, and at all
seasons of the year, and before the disease
makes its appearance. This We find not proved
in the orchard.
In some orchards the Blight of the same va
rieties is much more destructive the same sea
son than in others.
There is natural cause for this. Let us try
and discover it, and then we can act Intelligent
ly in preventing, or remedying the disease.
1t Is law of growth. that the upright shoots
on the top of the tree, as well as those growing
from the ends Of the limbs, put forth leaves
md grow much more rapidly than those ex-
tending In horizontal direction. This is evil
IDENTIFY caused by the excessive stimulant Of
lightonthe first expanded leaves, enabling them
to evaporate the water then in excess In the
crude sap, exhale the oxygen, and form the
true sap to descend with Its life sustaining pro-
perties.
We must recolleot the leaves of the Pear
make their appearance Immediately alter the
blooming season, when the ovule has been fer
tilted, and not only the flesh Of the fruit, but
the starch formed the previous season in the
true sap, has also been fertilized by the large
| amount of pollen absorbed through the calyx,
thereby rendering available and active thxt
food already laid up to perfect the growing
crop.
When, in early spring, we have . week or
two Of warm weather, with bright light, the
leaves and tender succu.ent shoots put forth
very rapidly, those tender leaves are then ena-
bled, in the light, to elaborate true sap; but
when this warm weather is followed by o few
days of heavy cold rains, and cloudy weather,
no true sap can be formed. The ascending sap
with its excess Of oxygen, is forced, with its
acid properties, to descend in the channels of the
true sap, making only watery growth; no
starch is formed to sustain this growth, the
roots In the saturated Soil, imbibing little DO
sides air and water!
When, however, a few warm days with bright
light follow, the evaporation through the leaves
and green twigs, this excess of water in tie
sap is so great, as to reduce the temperature
in the leaves sufficiently to destroy their tender
texture.
Sometimes only the tender growth is affect
ed; at others, 1t extends considerable dis
lance down the limbs. while in other cases, I'M
der excessive stimulants, the whole tree is de-
stroycd to the roots.
or by evaporation. Water, in porous vessels,
is rapidly cooled, if placed in the sunshine.
At the first appearance of Blight the leaves
are suddenly wilted as if frost bitten.
Theories are worthless without facts to prove
them. Some twelve years ago, during the
winter, load of manure was placed in few
feet of young Bartlett Pear tree; in the
spring, the whole tree was forced into excess
i've wood growth, much more succulent than on
h. Do Iatftcv Nn haAa hliohtt,,,~
and this tree blighted and was killed to the
roots, while the effect on those near, was scarce
ly perceptible. From this lesson, l have
learned never to manure, or even pillow my
orchard until the blighting season has passed.
Let the soil remain closed, dormant and cold,
and retard, not only the blooming season q
week or two, but also the rapid growth of
spring. The effect has been, that my blooming
season has been retarded so as to save several
crops, killed for my neighbors, they blowing,
warming their soil, and fastening their bloom
ing season, and my avoiding almost wholly the
blight.
On soil naturally, or artifcially drained, this
excess OF moisture is not thrown into the
leaves. So, in all new countries, while the soil
is porous, and The water sinks below the roots,
blight is never known; neither are the insects
destructive, which only make their appearance
as scavengers, to feed on the diseased and. de-
composing secretions, as they do on the body
and limbs, when the bark has been punctured
or lacerated, and their numbers multiply with
the increased emulation, causing blighted
appearance on the bark.
Injudicious winter pruning causes blight on
the rapid growth following.
When pear or apple tree is planted, it
should be cut back, so as to form its head In
the orchard, and never after pruned, except af-
ter the blighting season, when the sap is in full
4hn hraI- -.