Oxford Democrat. [volume] (Paris, Me.) 1833-1933, 1917-07-03
Bean Anthracnose or crust. %
SUGGESTIONS FOB IT'S CONTROL.

SUGGESTIONS FOB IT'S CONTROL.
Stimulated by the high prices tha
beans are commanding and by the pat
riotic desire to help meet the need OF In
creased food supplies bean acreage hal
been markedly increased in Maine the
present season. A high yield per acre
10 even more important than large
acreage. This neoessitates careful cult.
vation and protection from disease. Ol
all the disease that beans are subject to
in different parts Of the world, the most
common and most destructive disease re.
ported year after year to the Maine Agri.
cultural Experiment Station is anthrac-
nose or as It is most generally called by
Maine farmers "Rust." This 10 not Q
real rust for true bean rust rarely occurs
In this state.
Bean anthracnose is caused by q fun
gous parasite which lives over winter 10
the seed and Is spread and propagated In
this way. It's virulence is markedly In
fluenced by weather and soil conditions.
Rainy, cloudy weather and naturally wet
land is favorable to its development.
Conversely Il causes relatively much less
damage 10 dry seasons and on naturally
dry soils. The common notion that
working among the plants when they are
wet with rain or dew is we'll founded.
II the surfaces of the plant parta are wet
the spores of the fungus stick to them.
terminate In the Aim of moisture there.
on and Infection readily takes place.
Working In the plants at all times tends
to distribute the spores from the healthy
to the diseased parts Of the plants but II
the latter are dry the spores either do
not stick to them in great numbers or
they dry up and die before being able to
enter the leaf.
Much of the most important injury
from bean snthracnose occurs early 10
the season and is often overlooked. The
frat evidence of the disease in spring and
early summer Is on the conyled0ns or
''seed leaves" of the young plants which
grow from infected seed. Soon It begins
to appear on the young stems, and on
the petioles and under sides OF the viens
of the first foliage leaves formed, appear
ing as spots or more or less elongated,
brownish streaks. From there 1t spreads
to petioles and veins of the leaves pro-
duced later and finally to the pods after
they have begun to elongate.
1t is more noticed by farmers and
gardeners from midsummer on, on
account of the conspicuous, rusty or dis
colored spots on the pods, particularly
on those varieties which produce light
colored pods. The spots first appear IA
small, brownish or discolored areas With
purplish edges which enlarge and form
pits or ulcers as the result OF the drying
out of the tissues.
Anthracnose Ia not easy to control and
like similar troubles prevention rather
than cure Is the way to handle It. 1t ts
spread from year to year by means OF the
aeed. With seed free from all traces OF
anthrscuose the disease will not appear.
Also some varieties are much more re.
sistant than others. This phase will be
discussed In another letter In this seriea
later In the year with the view OF grow
ing better seed for use In 1918. The i'm
portant thing now Is to keep the beans
that are planted protected from attacks
of this disease as far as It is possible to
do so.
In the frat place the crop should not
be cultivated nor work of any kind car.
ried on among the plants when they are
wet with rain or with dew. II they have
been planted closely in drills 1t may be
advisable to thin out the weaker plants,
particularly those which appear to be
diseased, In order to allow greater access
of air and sunlight.
Although there are different opinions
as to the effectiveness of spraying as .
preventive measure the Maine Agricul.
ture Experime ent Station recommends the
use of Bordeaux mixture of the same
strength as used for patatoes. The first
application should be made az soon as
the first foliage leaves have attained fair
size, and repeated three times or more at
intervals of week or ten days. 1t is
important that the first application be
made when the plants are quite small.
Auy good potatoe spraying outfit will do.
For the first application use single
nozzle, run close to the row so as to do
thorough work and not waste the mix
ture. When the beans get larger two
nozzles per row are necessary as they
should be so adjusted that they will
thoroughly cover the whole row with the
spray.
CHAs. D. WOODS, Director.