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FERTILIZATION  EXPERIMENTS. 
Very  extensive  fertilization  experiments  are  being  undertaken 
chiefly  by  means  of  pot  culture.  Much  original  work  is  being 
done  in  this  direction.  Comparatively  little  chemical  fertilizer  is 
used,  the  chief  source  of  manure  being  oil  cake  meals.  Of  these 
the  most  important  are  cotton,  rape  and  soy.  Night  soils  and 
all  animal  manure  are  most  carefully  applied.  Green  manuring 
operations  are  also  understood  and  very  generally  employed. 
The  chief  of  these,  a kind  of  clover,  is  known  as  ‘Genge’  ( Astra- 
galus sinicus)  and  is  almost  universally  employed.  The  soy  and 
common  broad  bean  are  also  occasionally  used  for  this  purpose. 
GENGE. 
The  Genge  seed  is  sown  broadcast  among  the  rice  in  the 
autumn  just  before  the  crop  commences  to  mature.  By  the  time 
of  rice  harvest,  the  genge  has  germinated  and  is  well  started.  It 
is  then  mulched  with  straw  and  under  favorable  circumstances 
makes  a luxuriant  growth  by  the  following  May,  when  it  is 
ready  to  be  turned  over.  If  the  genge  crop  is  heavy  one  acre  of 
this  plant  is  sufficient  to  green  manure  four  acres  of  rice.  Forti- 
fied by  the  use  of  composts  it  forms  one  of  the  chief  fertilizers 
of  the  Empire.  If  the  lands  are  lacking  in  certain  constituents 
a suitable  cpiantity  of  oil  cake  meal  is  used  in  addition.  After 
hundreds  of  years  of  successive  cropping,  the  Japanese  rice  fields 
are  by  the  above  means  rendered  more  productive  than  ever. 
INSECT  PESTS. 
Several  serious  diseases  and  insect  pests  menace  the  rice  in- 
dustry in  Japan.  The  imperial  government  maintains  an  experi- 
ment station  solely  devoted  to  this  department  of  research. 
Stringent  control  measures  are  in  operation  and  have  done  much 
to  check  the  spread  of  pests. 
Stem  borers  do  considerable  injury  to  the  rice  industry.  Two 
types  are  conspicuous  and  when  they  become  established  are 
liable  to  destroy  half  the  crop.  They  are  fortunately  affected  by 
parasites  or  their  ravages  would  be  very  excessive.  The  con- 
trol of  plant  diseases  being  under  government  control  the  burn- 
ing of  infested  crops  is  insisted  upon  by  law.  After  harvest  the 
insect  retires  to  the  root  of  the  plant  and  the  stubble  being  burnt 
much  benefit  is  derived  from  this  measure. 
BLIGHTS. 
Several  blights  occur  which  are  liable  to  cause  much  injury  to 
the  rice  crop.  Of  these  may  be  mentioned  a disease  which  causes 
