Variation in yield and quality
  A
of [0133600 gPOWI1 011  
different plots reveals J
I t f S °l St t  
IIlpOI' EIHCB O O1 I`llC llI°€ _;
Q
By WILLIAM G. SURVANT *7
It is probable that deteriorated soil structure is lim-     , •• _
iting the income received from many Kentucky farms. , cf),  5 V 7;
Recent studies at the Kentucky Agricultural Experi-           _ *
ment Station have shown that yield and quality of '°‘*” Z if    tl       °  _   I
tobacco are lowered when structure and related phys-  3 - ‘z>-. $_r ·  ag, -._;  r ‘·   \   _ Fw
. . · . . . `. H V   '`AA     '   ” "     `¤_ M
ical properties of soil have deteriorated. These stuthes {   ..   *2   .a. Q7  ,   e Li
. . . - , . ~     =>;      ’ " I av  ` ii—r . so ·
also reveal that intensive use of land for row crops * xy  {JQ-..__§     ****2   w e  t; P
results in less favorable structural conditions in so1ls.         a··_‘ g       ¤· ~·~      
On the Experiment Station Farm at Lexington, com-   ’        ‘     ‘.`‘       j `  · __-_   __,_   (  
parisons were made of yields and acre-value of to-   M            -      {
bacco grown on a soil when structure and related   ir .3, V E _=   I    i   ls
physical properties varied. There was a close correla-      _j Y V` _ “     _-`r   1      
tion of yield and quality of tobacco with such Soil j_   j     1 A ..‘·° ‘ t
properties as permeability ( rate at which water moves `.         j'     .-._   ‘·° 1 _   ``.-.   A r
through the soil) and degree of aggregation (propor- if   Y '7 lplpp     — .
tion of the fine soil particles formed into stable crumbs \/;#°   ...·-i     ‘   st
or granules). The data in Table 1 show these rela- " °’   ‘°  `“ `   ‘ r
tiOuShipg_ Good yields of high quality tobacco like this require l`avor· ‘ V
able physical conditions in the soil in order for the plant
, _ te use the su > alv of nutriems effectively.
Table I.- The Response of Burley Tobacco to Variations ) ll ' '
in Degree of Aggregation and Permeability of a
Maury Silt Loan; Soil Table 2.-— The Influence on Degree oi` Aggregation and L
ii;i* "¤¤‘; ---- is--rr T;T; i"Ti' Permeability of a Maury Silt Loam Soil of Diiierent .
I)l:¥°`° p(,nm,umh,\. B`"l°`Y1°l”`°°" Intensities of Cropping ¢_
.~\g1Lre1.{ation to water U Yield .~\ere—value    
mee cc‘o m*4·‘m·"*r"c   r4·re"*L—·rm · ~ ,   , 6   . ——~—f n-· . °Z
65.6% 4.62 mem/1.r 2266 ii) $12.33 ,_-w¥2i‘*#£>&E-e2..-..2 ...... .. .   -i?*’*"i***`“*-‘· ew
.[2_Q¢%, r;_()1 " [888 " (Ogg lobacco after 50-yr. old bluegrass sod .... 65.6%   LH., lr. _ W] 
gg_5% 26;; " [757 " 714 Rotation of Tobacco-small grain-sod ........ 42.9% ‘. (   ifi *%@fY'l
165% {gg " (gh] " 474 Tobacco each year for 18 years .................. 29.5% in     $.01*
—- --——— — —--— ~ — -— - - - Tobacco each year for 50 years ................ 16.5%   mfé ri  
. . . . . . .   TQTTT  T   IT Y T T.   .'  Y m’*
'lhe intensity of use of land for row crops influences on 5omc PhY$*c¤l P1oPc1Uc$ et the ¤o1l 1* 511oWo io y
the physical properties of soil. The extent of deteriora- Tablc 2- ‘ _.(
tion of structure and related properties was determined Chcmgcs io fcmhtY r€S¤1¤¤g from thc ci`oPP1US SYS" b
on plots used for burley tobacco. These plots included; tcm mc not cUUYclY Ycspooslblc for dlgcrcoccs m gi`
(1) tobacco after a bluegrass sod over 50 years old; yields after Sed ci'oP$· This was mdlcatcd by comPm" ,-
(2) tobacco grown in a rotation with small grain and ing thc i`c$Poo$c of thc tobacco cl`oP to <1ift€r€r¤t fcc A
()I·Chnr(l grass vyith {Cd Cloygy;   tobacco vyhcsrg   llllty levels ()ll plots 1Iz`t\’lIlg 1l1Tl`21.VO1°}.1.l)l(i` Physical COI]- `
crop hm] hwh gl-hwh ouch yuh- fm- 18 Yams with H ditions resulting from intensive use with the response 4,
Cover Cmp hftm- Ouch Crop of thimcch. nm] (4) tO_ of the crop on unfertilized land on which physical l`
bacco wm.!-C this Crop hud hhhh gmwh (inch yeh]- fm- conditions were favorable. Table 3 summarizes the (_"
about 50 years with a cover crop after each crop of dum from fills comparison- _
tobacco. The influence of these cropping programs ((;(mmm(,(] 7,,, pugt, 12) N.,
~.
6 l