The sun., 1919-10-05


OF soil bacteria as a part Of the soil
for producing soluble plant
food, 1t is sufficient to say that In so
far as any soil has an effective bac-
terial machinery 1t is fertile, and in
10 far as 1t has a defective machinery
II is almost certain to be unfertile.
Hence, If protocol destroy large num-
bers of soil bacteria and interfere with
their activities the supply Of available
plant food must of necessity be re-
duced and crop growth unfavorably
affected thereby.
Whatever tho explanation for the
failure of rich garden soils to offer
satisfactory conditions for plant
growth, 1t has been clearly demon
strated that certain treatment of such
garden soil may restore their former
fertility. 1t has been demonstrated
time and again that soil partially
sterilized by means of steam or by
volatile polsons like chloroform, ether,
carbon bisulphide, alcohol and SO forth
soon after develops a truly remark
able fertility. Some investigators have
attributed this increase in fertility to
the destruction of the soil protozoa,
which are more readily injured by the
heat or poisons than are the bacteria.
The removal of the protocol leaves
way open for the unhindered increase
OF the bacteria to astonishingly large
numbers and the production by them
OF abnorma1ly large amounts of avail
able plant food. Other investigators
a hA aff ~
ton by the heat or by volatile poisons
of a toxic product which may have ac-
cumulated in the soil. Still othehs
think that the effect of the heat or of
Volatile poisons is the making soluble
Of soil compounds containing plant
food ingredients. Again there are
those who believe that the soil treat
ment In question destroys some of the
bacterial species in the soil and per-
mits the multiplication of those whose
activities are most favorable for the
growth of plants. Be 1t as Il may,
tho treatment of soils with steam or
volatile antiseptics has become an
established practice among progress
sive growers OF vegetables under glass
The steaming of soils or of their treat
ment with volatile antiseptics in so
far as these soils are located out of
doors has not yet become an estab-
lished practice. The possibilities that
lie in such treatment of garden soils
particularly such as have been richly
manured for many years, have already
been revealed by numerous expert
ments.
1t is now proposed by Georges Truf-
faut OF Versailles. France, to make the
practice of partial soil sterilization a
common one in French gardens. Fol
lowing the example of investigators I'm
Europe and IN Mott America he has
tested large number of products
which have given more or less promise
as means for partial soil sterilization.
He thinks, for instance, that cyana-
mid, ono OF the new heterogeneous fer
tillzers. is likely to prove a valuable
material for this purpose. Evidently
the Same conclusion has been reached
by the Florida Experiment Station,
since cyanamld has been employed In
Florida for some time as an effective
means for Kidding the soil OF the de-
itructive eel worms or nematodes. A
number of coal tar derivatives have
also been tested out at Versailles and
have given promising results. The
most satisfactory and economical re-
turns have been secured to date from
mixture of sulphide of lime and of
one OF the coal tar products. BY using
$50 to 200 pounds of sulphide Of lime
with so to 100 pounds an acre of the
coal tar produCt in question Mr.. Truf-
faut has been able to show strilxingly
beneficial results. The writer OBJ
served the effect of this treatment both
in the greenhouse and in the garden
for crops like tomatoes, potatoes, egg
plants, oats, melons and a number or
other crops. Mr.. Truffaut now pro-
poses to establish plant for the man.
ufacture of materials to be used for
the partial sterilization OF garden soils.
He expects TO have in operation the
coming fall one or more kilns for the
burning of land plaster, which Is, as is
we'll known. sulphate of lime. From
land plaster sulphide of lime can be
made readily IN these kilns at a slight
cost It would seem, therefore, that we
are likely to behold in the next half
dozen years an increase in the use OF
materials for partial soil sterilization,
not only in greenhouses but in gardens
whose soil Is so rich in vegetable and
animal residues as to hinder the most
vigorous growth Of plants.
Through such treatment many OF
the difficulties encountered in small
gardens will no doubt be overcome anu
soils maintained in a healthy condi-
ton.