South Bend news-times. (South Bend, Ind.) 1913-1938, 1917-01-21
CROP ROTATION
KILLS PARASITE

by specialists in the United State
department OF agriculture as "a means
OF controlling the beet-sugar nema-
tode. a pes; which has been known
TO close a number of beet-sugar fac
tories in Europe. and is already suf-
fciently prevalent IN the United
States 10 be a serious menace 90 the
industry. The rotation should i'm
clude beets or other suspected crops
only once and il is regarded as
safer FOR the farmer 20 extend il 90
six years rather than 10 content
himself with four OF five years-the
common European practice Ia
farmers bulletin 7I2. The Control
of the Sugar beet Nematode." a list
OF the crops suitable for such a roe
tation in the various sugar-beet re-
gions OF this country is given.
Sugar beet nematodes are exceed
ingly fne thread-ukC. colOrless Crea-
lures, so small that except under
certain conditions. they can not Dee
discovered by the naked eye. When
they first hatch from the eggs they
md their way TO the nearest rootlet.
force their way into IL. and proceed
10 feed upon the plant juices This
ultimately results i'm the production
of a characteristic dense mass OF
rootIets. condition which in Eu-
rope is described as hunger roots.
bearded roots. hairy roots etc.
In severe cases the beet itself is
stunted and resemble the root OF
celery plant. For this reason BE- is
sometimes called celery root"
Change i'm Foliage.
The first evidence. however. of the
trouble that is likely 10 be noticed
by the farmer is the change In the
foliage Toward the end OF July or
early I'm August infested areas be-
come lighter in tint, the leaves 90
the affected plants droop until they
lie prone upon the ground and Dc
not recover during the night The
outer leaves become yellowish. spot
ted. and generally discolored. Ulti-
mately they wilt and die. TIE inner
leaves fail 10 reach their normal size
and may die as we'll I'm severe
cases the whole plant is destroyed
and sharply defined bare spots are
left in the beet fields.
The reduction i'm the crop caused
by this pest is very great The av-
erage weight Of foliage OF sugar
beets infested with beet nematodes
may fall as low as one-hfth that oi
healthy beets and the average root
weight suffers in proportion. Fur
thermore, the content OF sugar is
very materially reduced. Expert
ments have shown that an average
OF 14.9 percent OF sugar in healthy
beets may be lowered 10 S.4 percent
in badly infested stock.
Once the sugar-beet root nema-
todes has been introduced into a
district. il is easy for the pest 20
spread. Infested soil may be car
ried from bne field 20 another In a
number of ways. one OF the most
common being the waste water from
sugar factories owing to the fact
that the eggs are frequently pre-
served in brown cyst. or sack. into
which the female ultimately turns
and which ehectually protects them
from the cold. they may continue in
"A
sometimes even years. and this Oh
viously greatly facilitates the dis
semination Of the pest. For this and
other reasons IL is essential that a
rotation OF crops adopted 10 elimin-
ate the nematOde should be- contin-
ued for five years or more
Zone Divided Into Groups.
a
the beet zone OF the United States rs
divided into four groups. These
groups and the crops suitable for
use in rotations i'm each area are as
follows:
Cd California and Arizona.
90 OREGON and washington.
CD Utah. Montana. Nevada. Col
orado, Kansas. and South Dakota
90 Nebraska. wisconsin. Indiana.
Michigan, Ohio. New York and West
Virginia.
Group I.-Cowpeas. SOY beans.
sweet clover. rye. the millets. toma-
toes. asparagus. lettuce. cantaloupes.
strewberries. barley. corn. lima
beans. wheat
Group 2.-Cowpeas. SOY beans.
sweet CloA tfB rye the lllllfIr, LiA|A
crops Csuch as lettuce and aspara-
gus. but not celery. barley. wheat
Group 3.-In addition 20 the crops
mentioned in group cantaloupes,
Cucumbers. and potatoes.
Group Glover. cowpeas, sweet
clover. SOY beans. rye. the mIlets.
tobacco. fax. peppermint. cucum-
bers. straw berries. melons. lettuce.
asparagus, some other truck crops.
the grasses with the exception Of
tall oat-grass. barley, corn, lima
beans. potatoes and wheat
Where only small areas are found
infested. the adoption OF a crop r0-
tation may be avoided BY immediate
action survey OF suspected fields
should be made as soon as the hot
season has set in. Wherever WILT
ing and yellowing Of the leaves IS
noticed. the beets In this area and
those for several feet around should
be pulled and destroyed by GOVERNS
with quick lime. A narrow trench
about one foot deep should then bs
dug around the area and flled with
unslaked lime The ground inclosed