The free lance. (Fredericksburg, Va.) 1885-1926, 1906-06-21
COMMERCIAL FERTILIZERS
Address on This Subject BY Or. C. U. Gravatt, Of
Caroline.

cr- Club Of Port Royal. which attracted
mnch attention.
Commercial Fertilizers in General, :. >
>. in Particularly Most people. il ask.
cd what il the first thing absolutely
necessary for the ~pruuting ol good seed
aud lac growth oi plants. would reply
earth to plant tlc seed in Vet 1t las
been ahuudantly proven 10y "a series ol
most interesting work that earth IL not
e-sential either for termination. develop
ment or iruiting
Not only has large variety f plants
including corn. " heat, oats, barley and
buck wheat. been successfully grown aud
a full complement OF wrlimalund grain
been gathered from plants that never
were in contact with thr soil at all. hut
even trees of considerable height have
heen so reared.
We know there are immense tracts OF
desert with scarcely a vrstige
oi vegetation. and We al-O know that
even rich soil may be- rendered harr-n 10y
exposure to heat sufficiently intense to
DESTROY it, organic matter. Earth may.
therefor. h.. considered ~ "a reservoir
or -torehOusc for plant food. Just ~ "A
barn IL storchousr for the food ot man
and beast. and ~ a means of physical
support
Planr-iood consists of l3 elements,
phosphorus, silicon, sulphur chlorine.
iron. lime. magnesium, sodium, potas
stun. nitrogen hydrogen, oNN Ng'n nnd
carbon They are called 'plant-ioods.
because they are always found M great
er or less proportion iu all plants. and
nature does not provide IN chanc" hap
hazard way. Nin. Oi them ARE derived
from the soil. VIZ. phosphorus. 81 icon'
sulphur. chlorine. lime. magnesium. iron,
sodium and potassium. Nitrogen. PR
mariN gathered from The air,i- ioumd n
the humu- or drcaying vegetable matter.
Water supplies the oxygen and
hydrogen 10 the roots. Carbon
comes from tie air. Fortunately
the greater part of these elements al
WAYS exists in the soil inquantliies mort
than sufficient for tine need of plants
Four OF them arr often deficient, how
ever. or, II present, they may not be- 10
condition for ready absorption. These
iour are phosphorus. nitrogen. potas-
sium and lime. often called essentials
and arr the ones 20 br specially conSld-
cred in the fertilization of land
is noticeable, that fertilizer analysis
nearly always gives ammonia instead oi
nitrogen. Now. ammonia II not taken
mp by plants IA such IL must first bc
converted into nitrogen and nitrates.
and the resulting nitrogen il little more
than H. of the amount of ammonia.
But for advertising purposes > per cent.
ammonia sounds larger than per cent
nitrogen lu other words. "a mere trick
OF the trade
Fertility. upon which crop pro
duction rests, depends upon the
amount aud proportion OF the
different plant-inods contained in
the soil. We speak OF rich and poor or eN-
hau-ted soil. meaning thereby one that
i abundantly IS supplied with the essential
elements or one that il deiirientl ia one or
more of them ! say one or more because
all Of the iour principal ingredients must
be- present. Some of the minor ones may
be- deficient without seriously affecting
growth, but If even one OF the four r.
ierred 10 be- absent or grossly lacklng,
plants cannot thrive. Furthermore there
must be- a fair balance between them.
Excess Of nitrogen. for instance, causes
large leaf and stalk Development, but ~
duces yield.
Crop prOductivencss il, with proper
tillnge. in direct relation To the amount
Of suitably proportioned food. limited
only by the absorption capacity oi
plants and proper water-hOlding
capacity OF the soil.
The maintenance or improvement OF
fertility. which constitutes one Oi the
chief distinguishing features between
scientific and unscientihc farming, con
sists in 80 employing manures and
commercial fertilizers a. to keep the land
M To its present standard OF productive
ness or To- increase it. Here is problem,
in the solution Of which thought must
be- given. keen Judgment displayed and
science invoked. Here is a parting oi
the WAYS between success and unsuccess
one road leading to prosperity, the
other inevitably to disappointment and
loss. The choice is with each farmer ~
10 which road he will follow.
The agricultural value Of fertilizer,
which is to be distinguished from its
commercial value, is determined by the
increase Of yield due 10 its use and this
can only be- arrived at by a comparative
teri. For example-300 pounds OF II
percent. acid phosphate worth 81 10 is
appliel To wheat. To counterbalance
this cost 3 bushels of wheat over and
above what would have been made with
out the fertilizer must be made. Armoby
saws: "The most satisfactory method by
which we can determine the needs OF q
soil il to ask the question Of the soilit
by growing "A crop upon il with different
fertilizers and noting results. Such soil
tests have, in many cases, given results
OF much immediate practical value for
the locality IN which they were under
taken. As a rule, however, farmers have
looked upon such experiments az some
thing too costly and complicated and
consequently have been content to use
fertilizers in q more or less haphazard
manner, and in many cases, no doubt, at
a great financial disadvantage"
Soils differ greatly in their needs for
specific elements owing to their treat
ment and cropping or to their original
formation. Generally speaking n sandy
soil is deficient in all the essential plant
food constituents. A clayey soil con-
tains the mineral elements in abundance,
particularly potash while a soil very
rich in vegetable matter is apt to be
deficient, or relatively so, in mineral mat
ter, and limestone soil is usually well
supplied with phosphoric acid. These
may be taken as general guide rs to
the kind of fertilizer to use.
The difference between q good brand
of fertilizer and poor one depends not
only in the analysis, but largely on the
quality of the materials of which it il
made. Thus the nitrogen in one brand
may have been obtained from nitrates
or the ammonia salts, in another from
leather. horns, wool waste, etc In one
the phosphoric acid may be in the form
of unheated bone or rock phosphate and
very slowly soluble, in another, in the
form of superphosphates aud quickly
available and 80 on.
With these preliminary observations
we will examine the latest State bulletin
dealing with commercial fertilizers. 1t
Il proper TO state that the Commissioner
of Agriculture publishes the list not only