Atlanta semi-weekly journal. (Atlanta, Ga.) 1898-1920, 1911-08-01
WHAT VARIOUS CROPS
REMOVE FROM THE SOIL


cabbage will take from the land 100
pounds OF nitrogen. and two tons of
alfalfa hay. IS pounds of nitrogen.
Thefe is this difference. however. in
that the alfalfa is supposed to elaborate
the greater part OF it's nitrogen supply
fro mthe air, whereas, the cabbage crop
must secure all OF it's nitrogen from
the soil. 1t viii be observed that ali
the leguminous crops are heavy users
OF nitrogen, but as they do not exhaust
the supply OF IL in the soil under ra-
tional conditions, they may be made 10
build up the land and supply IL with
this essential element for such crops as
tobacco, timothy hay, cotton and cab
bage- A glance at these figures reveals
the importance and value OF a CROP ro-
tation. and shows why this system
should be adopted as rapidly as possible
on every farm.
An examination Of the amount OF
phosphoric acid and potash removed by
various crops shows the same wide
variation. as has been indicated with
nitrogen. For instance, cabbage will
take IS pounds OF phosphorus from the
soil. whereas. 100 bushels OF potatoes
vii ltake but 10. and 1000 pounds or
leaf tobacco but s. Most crops do not
take as much phosphorus from the land
potash. but II will be seen that cabbage
Is a very exhaustive crop to this par
ticular element. 1t appears that can
bage also requires very large amount
OF potash. is tons taking 1s5 pounds OF
this element from the soil Legumin-
Gus crops also draw heavily on the pot
ash supply, two tons of alfalfa hay re-
curing IS pounds of this element, ana
the other crop proportionately larger
amounts than are required Of phospho-
rus
1t appears. therefore, that the farmer
who adopts a rotation OF crops on his
soil may easily increase its fertility,
keep IT in better physical condition, ana
make II possible to secure larger crops,
without depending exclusively for his
plant food supply on commercial mate
rails. There is no objection to usins
commercial fertilizers. but they do not
change the mechanical condition nor IA
vorably affect the life activities of the
various bacteria the existence of which
in the soil Is necessary 10 the welfare
OF many Of our crops. On this account
rotation becomes as essential to the
development OF a permanent system or
agriculture as any other factor.
COTTON RED SPIDER.
A. n. NJ, Toccoa, Ga, writes: I am
sending two cotton leaves taken from .
six-acre field OF cotton. You will notice
the red spotches on IT, and II has hun
dreds OF almost invisible insects on It.
The leaves are from a field near mine
and the trouble has taken the entire
field. The field is over mile from
mine. but I wish to be posted so If L
attacks my crop I will know what to
do. My neighbor says he noticed q
fox Lac Ia cf hut ma
no attention to IL. Can you give US any
light on the subject?
The specimens sent as you can imag-
inc, are very much dried up. and there
fore. II is difficult to positively identi-
fy the cause OF the trouble, but un-
doubtedly from what you say, the cot
ton is affected by what is known as the
red spider, a mite which early in July
cotton fields In widely separated sec
lions OF Georgia, and the damage it
does is sometimes confused with the
rusting OF cotton, which may be due to
the poverty OF the soil In vegetable
matter or potash.
The red spider Is TO be found, as a
rule. congregated along the veins Of the
lower surface OF the leaves OF cotton
plants where they feed by puncturing
the leaves and sucking the juice. A
thin network OF web is spun over the
surface on which they feed The In
sect lives over from year to YEAR on
any green vegetation And. passes the
winter in the adult stage. and has even
been known to propagate at tempera-
lures slightly above freezing. This in
formation indicates one Of the best
ways OF destroying the psst. namely the
removal and complete destruction OF all
vegetation In the vicinity Of affected
areas. This is a very important mat
ter. and had your friend taken the
precaution the chances are that his cot
ton field would not have suffered as IL
appears TO be doing at the present time
Moreover. careful watch Of the field
should be kept. and at the first evil
dence OF the appearance of the spider
any affected plants should be pulled up