The Wisconsin tobacco reporter. (Edgerton, Wis.) 1877-1950, 1917-03-23
NOTE BOOK SKETCHES

C0nfznHe1 TOM LdSt 10eeR.
The grower, however, was very
frequently justified financially in sac
rifcing quality for yield. On the other
hand, the packers and manufacturers,
who looked for certain good grades and
quality Of leaf from certain sections,
were frequently disappointed and some
times Withdrew from the buying field.
Fortunately, the growers often found
a ready market for poor qualities of
tobacco with other manufacturers as
''stemming stock at lower price.
The growers, however, found the old
"worn out" tobacco soils altogether too
fertile to grow oats without lodging,
and that they would grow the best
crops of corn on the farm. These OBJ
servations forced the farmer, and
sometimes the soil specialists also, to
the conclusion that the tobacco crop
had not exhausted the soil of it's fer
tility, but removed some particular ele-
ment, which it needed, but which other
crops did not use, or, that it added
some injurious substance to the soil
poisonous to itself but not to other
plants. These theories also may now
be abandoned from practical cOnsldera-
tion in view of the facts established as
a result Of more recent experimental
work in studying this condition in to-
tbaccO culture.
The root rot disease is responsible
either directly or indirectly for large
majority of the tobacco crop failures in
recent years.
Because of the danger of confusing
such factors as improper tilth, fertility
and moisture relations with the condi-
tions brought about by the root rot
disease, they will be discussed briefly
before considering in detail the nature,
cause and possible remedy for this dis
ease.
WATER INFLUENCES YIELD AND QUALITY
OF LEAF.
1t is matter of common observa-
tion that the amount of moisture in the
soil influences to marked extent the
yield and quality of the leaf. The
amount of water which soil receives
is dependent, except in irrigated areas,
UPON the rainfall. The amount of
water which remains in the soil, how
ever, is in large measure dependent
upon how the soil is prepared and cul-
tiyated. The physical character, in
.cfuding the humus content, also deter
mines to great degree the per cent Of
moisture held by soil. Tobacco is
grown on soils of quite different water
holding capacity. i Certain types of leaf
are best grown on soils with z to s per
cent moisture, while others develop
best on 20 to 22 per cent moisture. If
the moisture content remains much
above or below these percentages for
any considerable time, the leaf is likely
to suffer in yield or quality. The moist
ure of course varies from day to day and
season to season, but the best growers
maintain as far as possible uniform
supply of soil moisture either by drain
age to remove excess water, or by ju-
dicious preparation and cultivation of
the tobacco soils to prevent loss of
water.
ROOT ROT DISEASE STUNTS PLANT
GROWTH.
In soils where all conditions appear
to be favorable for the growth of the
tobacco crop, and the plants become
stunted in growth, or show signs OF
premature topping out or ripening, the
root rot disease is usually responsible.
The development of the disease is fav-
ored by wet weather, although it's ef-
fects may often be noted better follow
ing short season of drought preceded
by excessive rains. The plants have
all the appearance of suffering from
lack of sufficient plant food and soil
moisture. If the plants are pulled
from the soil, the root system will be
found to be small or showing Drowned
and blackened decayed areas. 1t is
evident that this lack of root system
and diseased condition of remaining
roots interferes with the normal nutri-
tion of the plants. The plants conse-
quently starve. regardless of the state
of fertility or the moisture content of
the SOIL The extent of the starvation
will vary with the amount of disease
present. A small amount of the dis
ease on the roots may show no material
decrease in yield or quality. Slight
checking is usually indicated by curl
ing of the margins of the leaves, or
early r1pening and yellowing of the
lower leaves. On the other hand, the
plants may be so seriously affected as
to make no growth whatever during the
entire season. The plants do not u.s.
ually die, but hang tenaciously to life
by means of sending out new roots to
replace those which rot. The most
common condition of the crops, how
ever, in infected fields is an intermedi-
ate degree of stunting, and ''poor,
eight" or ''half" crops result.
Another common indication of the
presence of root rot is the unevenness
of the growth of the plants in the field.
This may be due to varying soil condi-
tions as affecting the amount of disease
or to differences in resistance of indi-
vidual plants to the disease. The lat
ter condition usually happens where
impure or mixed seed is used by the
grower. If seed of pure strain of a
variety is used, the plants will usually
present an even degree of stunting. A
large amount of damage from root rot
comes indirectly through injury to
quality of. "a crop normal in size. This
is brought about by the peculiar condi-
tion so often observed whereby the
crop remains at standstill during the
e h. md fnr