Report  on  the  Field  and  Feeding  Experiments  at  Woburn.  223 
In  conjunction  with  minerals,  nitrate  of  soda  also  gave  a 
heavier  crop  on  plot  6 than  salts  of  ammonia  and  minerals  on 
plot  5,  which  produced  47^  bushels  of  barley,  weighing  54  4 lbs. 
per  bushel,  and  33  cwts.  3qrs.  and  4 lbs.  of  straw  ; whilst  plot  6 
gave  501  bushels  of  dressed  corn,  weighing  54^  lbs.  per  bushel, 
and  36  cwts.  and  24  lbs.  of  straw.  Although  the  same  nitro- 
genous top-dressings  were  applied  to  the  Experimental  wheat- 
plots,  the  ammonia-salts  last  season  had  a better  effect  upon 
wheat  than  nitrate  of  soda. 
Comparing  the  produce  of  plots  8a  and  9a  with  the 
average  yield  of  the  two  unmanured  plots  1 and  7,  it  will  be 
seen  that  7 bushels  more  barley  was  grown  on  plot  8a,  and 
7-7  bushels  more  on  plot  9a,  than  on  the  average  upon  the 
unmanured  plots. 
In  the  case  of  the  barley-crop,  the  large  quantities  of  minerals 
annually  applied  to  plots  8 and  9 thus  appear  to  have  left  a 
residue  of  available  mineral  plant-food,  which  has  had  a 
favourable  effect  upon  the  sixth  barley-crop. 
On  the  other  hand,  the  same  minerals  applied  in  the  same 
quantities  to  the  Experimental  wheat-plots  8a  and  9a,  as  has 
been  shown  before,  did  not  raise  the  produce  in  the  slightest 
degree  above  the  yield  of  wheat  on  the  unmanured  plots  1 
and  7. 
The  addition  of  a large  dose  of  nitrate  of  soda  to  the  minerals 
on  plot  9b  had  the  effect  of  largely  increasing  the  barley-crop. 
On  this  plot,  it  will  be  seen,  the  heavy  crop  of  nearly  69  bushels 
of  dressed  barley  and  about  49  cwts.  of  straw  was  grown 
per  acre. 
A very  heavy  crop  was  also  grown  on  plot  8b,  manured  with 
minerals  and  ammonia-salts,  containing  as  much  nitrogen  as 
the  nitrate  of  soda  employed  on  plot  9b,  but  the  produce  of 
dressed  corn  on  plot  8b  was  14  bushels  less  than  on  plot  9b. 
With  regard  to  the  plots  10a  and  11a,  from  which  the 
dung  was  withheld  in  1882,  but  which  had  been  manured 
with  rotten  dung  annually  for  the  five  previous  barley-crops, 
it  appears  that  the  residue  of  the  dung  applied  in  previous 
years  increased  the  yield  of  barley  in  1882  to  the  extent  of 
9-6  bushels  on  one  of  the  plots,  and  of  8-3  bushels  on  the 
second  plot,  above  the  average  yield  of  the  continually  un- 
manured plots  1 and  7. 
The  farmyard-manure  which  was  applied  last  January  on 
plots  10b  and  11b  slightly  raised  the  produce  of  dressed  corn 
above  the  produce  of  plots  10a  and  11a,  which  were  not 
dunged  in  1882  ; but  the  effect  of  the  dung  is  more  manifest  in 
the  increase  of  straw  than  in  corn,  especially  on  plot  11b. 
For  the  present  season  farmyard-manure  has  been  applied 
