Rotation  Experiment. 
293 
manures  it  gave  considerably  increased  crops,  the  heavier  dress- 
ing probably  proving  more  effective  in  consequence  of  the  heavy 
rainfall.  The  crops  obtained  with  ammonia  salts  alone  (2a)  and 
ammonia  salts  Avith  minerals  (5a)  are  practically  negligible,  the 
greater  part  of  the  plots  having  nothing  but  a covering  of 
spurry ; the  limed  portions  (2b  and  5b)  were  better,  but 
more  marked  was  the  difference  between  the  heavier  dressings 
of  ammonia  salts  with  and  without  lime  (8a,  8b,  8aa,  8bb). 
From  previous  applications  of  farmyard  manure  (11a)  marked 
benefit  was  still  seen,  this  plot  yielding  over  12  bushels,  as 
against  the  unmanured  produce  of  2 bushels.  The  straw 
throughout  was  very  short,  and  the  only  plot  giving  a fair 
yield  was  9a  (minerals  and  nitrate  of  soda).  As  regards  the 
valuation  of  the  corn,  the  four  best  lots,  at  the  head  of  which 
was  farmyard  manure,  were  considerably  above  the  average  of 
the  barleys  of  the  district,  but  the  low-yielding  plots  were 
much  below  this,  and  were  very  poor  samples. 
Rotation  Experiment  {Stackyaiw  Field),  1903. 
Barley  having  been  grown  for  a number  of  yeai’S  in 
succession,  the  land  necessarily  had  become  a good  deal 
overrun  with  weeds.  It  was  accordingly  decided,  now  that 
the  plots  had  become  very  fairly  uniform  as  regards  yield  of 
corn,  to  take  a change  of  cropping  and  grow  mangels  in  1903. 
It  was  hoped  in  this  way  to  give  the  land  a thorough  cleaning. 
Unfortunately,  as  is  now  too  well  known,  the  constant  and 
heavy  wet  that  prevailed  made  the  year  1903  as  bad  a one  as 
could  be  imagined  for  cleaning  land.  The  common  experience 
was  that  weeds  grew  apace,  and  there  was  no  keeping  them 
down  ; fields  left  fallow  were  as  bad  as  if  they  had  never  been 
touched,  ami  the  year’s  cleaning  was  practically  thrown  away. 
So  here,  though  a crop  of  mangels  was  grown,  the  land  was 
covered  with  weeds,  and  the  hoped-for  cleaning  could  never 
be  properly  effected.  During  the  winter  of  1902  and  spring 
of  1903  twitching^  ploughing,  cultivating,  with  scarifying  and 
harrowing  were  done,  and  on  May  13  “ Golden  Tankard  ” 
mangel  seed  was  sown,  at  the  rate  of  8 lb.  per  acre,  on  all 
the  four  rotations  (sixteen  acres).  Horse-  and  hand-hoeing 
followed,  but  it  was  not  until  August  1 that  the  mangel 
plant  could  be  singled.  One  cwt.  of  nitrate  of  soda  to  the 
acre  was  applied  shortly  afterwards,  but  no  other  manuring 
was  permissible  in  view  of  the  nature  of  the  proposed  inquiry. 
The  crop  Avas  ready  for  pulling  on  November  12-14,  shortly 
after  Avhich  date  the  roots  were  carted  and  Aveighed.  The 
results  are  given  in  Table  III.,  page  294. 
While  no  importance  attaches  to  the  particular  Aveights 
recorded,  the  hoped-for  cleaning  of  the  land,  oAving  to  the 
