Daodalbi-r  2i,  1898. 
JOUimAL  OP  RORTIOLJLTVUf^  AND  COTTAGE  GARDENER, 
uttendanco  »t  any  meeting  wa»  fourteen,  and  that  fell  in  the  provincial 
exhibition  season. 
Practically,  the  average  attendance  for  the  twenty -nine  members  who 
were  present  at  ten  meetings  and  upwards  was  thirteen,  which  was  not 
bad.  The  actual  result  of  this  record  is  tn  show  first  that  anything  like  a 
real  representation  of  the  provinces  on  the  Committee  is  practically 
impossible  because  of  distance  and  cost,  whilst  were  it  not  for  the  fact 
that  the  Committee  includes  a  large  contingent  of  metropolitan  members, 
or  those  residing  within  fair  distance,  attendances  would  be  so  few  as  to 
render  the  transaction  of  business  almost  impossible.  It  is  well  that 
any  who  may  henceforth  complain  as  to  poor  provincial  representation 
should  bear  this  fact  in  mind. 
It  is  not  possible  or  fair  to  pass  from  this  subject  without  expressing 
one's  warm  admiration  for  their  devotion  to  the  work  of  the  Boyal 
Horticultural  Society  as  presented  by  the  Fruit  Committee,  every 
member  of  which,  beyond  paying  1  guinea  for  his  fellowship,  and  a 
very  much  larger  sum  as  a  rule  for  travelling  expenses  and  needful 
refreshment,  has  to  spend  much  valuable  time  at  the  meetings.  Of 
course  the  Council  in  its  annual  report  thanks  the  members  of  the 
respective  Committees,  but  I  have  often  thought  that  the  Council 
might  recognise  the  work  in  a  far  more  hearty  way  by  inviting  the 
whole  of  the  members  of  all  these  bodies  to  an  annual  dinner  on  the 
evening  of  some  meeting  or  of  the  Temple  Show. 
There  were  five  meetings  of  the  Fruit  Committee  held  during  the 
year  at  Chiswick.  The  attendances  at  these  gatherings,  of  course  neces¬ 
sarily  small,  were  none  the  less  so  far  satisfactory  that  they  reached 
nine,  ten,  eleven,  twelve,  and  thirteen,  or  a  total  of  fifty-five.  Here 
twenty-one  members  attended  variously  ;  two  were  present  five  times, 
five  four  times,  three  three  times,  five  twice,  and  six  once.  Both 
Chairman  and  Secretary  attended  four  times.  Generally,  the  work  done 
at  Chiswick  is  very  important,  bat  much  in  relation  to  outdoor  things 
depends  on  the  season.  The  gatherings,  if  the  weather  be  fine,  are 
invariably  very  enjoyable,  and  it  is  s^^ldom  that  the  members  present  do 
not  find  something  of  great  interest  to  arrest  their  attention,  even  beyond 
the  special  subjecti  they  have  been  summoned  to  examine. — A.  D, 
HUMTJS  IN  ITS  RELATION  TO  SOIL  FERTILITY. 
By  HAETiY  Snydee,  B.Sc. 
{Concluded  from  page 
Value  of  Humates  as  Plant  Foou. 
The  value  of  these  various  forma  of  humates  as  plant  food  has  been 
the  subject  of  extensive  investigations,  and  many  of  these  experiments 
indicate  that  the  humates,  when  acted  upon  by  the  proper  micro¬ 
organisms,  are  very  valuable  forms  of  plant  food. 
At  the  Minnesota  Agricnltural  Experiment  Station  Oats  and  Eye 
have  been  successfully  grown  when  the  only  forma  of  mineral  food  were 
humates  of  potash,  lime,  magnesia,  iron,  and  humic  phosphate  and 
sulphate.  Hamate  material  obtained  from  rich  prairie  soil  was  mixed 
with  pure  sand,  which  contains  practically  no  plant  food,  and  gypaum 
was  added  to  prevent  the  formation  of  sour  humus.  The  mixture  was 
watered  with  leachings  from  a  fertile  field,  so  as  to  introduce  the 
organisms  which  usually  carry  on  the  work  of  humus  decomposition. 
Oats  seeded  in  the  soil  thus  prepared  finally  produce  fertile  aeeds,  the 
entire  plants  containing  fifty  times  more  potash  than  was  in  the  seeds 
sown,  and  over  sixty  times  more  phosphoric  acid,  The  only  source  from 
which  the  plant  could  obtain  these  substances  was  the  humates  added  to 
the  soil. 
In  experiments  in  which  the  soil  leachings  were  omitted  the  Oat 
plants  only  made  feeble  signs  of  growth,  plainly  showing  that  unless  the 
potaah,  phosphoric  acid,  &c.,  combined  with  the  humus  is  set  free  by  the 
action  of  micro-organisms  the  plant  is  unable  to  use  them. 
There  are  a  number  of  facts  in  field  practice  which  also  indicate  that 
plants  are  capable  of  feeding  on  humates.  The  roots  of  plants,  parti¬ 
cularly  those  of  grains,  will  always  be  found  clustering  around  any 
decaying  vegetable  matter  that  may  happen  to  be  present  in  the  soil. 
When  Wheat  or  Oats  follow  a  corn  crop  the  roots  of  the  grain  will  he 
found  in  many  cases  to  completely  encase  any  decaying  pieces  of  corn¬ 
stalks  that  are  present.  The  cornstalks  are  not  rich  in  plant  food,  but 
they  decay  in  the  soil  and  combine  with  the  soil  potash  and  phosphates, 
forming  humates  which  the  grain  feeds  upon. 
Large  piles  of  sawdust  many  feet  in  height  and  circumference  are 
frequently  left  around  sawmills,  or  the  sawdust  is  used  for  filling  in  low 
places.  The  sawdust  is  very  slow  in  decomposing,  but  in  time  it  is 
covered  with  vegetation,  which  must  obtain  most,  if  not  all,  of  its 
mineral  food  in  the  form  of  humates. 
Means  op  Increasing  the  Humates  op  the  Soil. 
Inasmuch  as  both  experiments  and  observations  in  the  field  appear 
to  strongly  indicate  that  plants  have  the  power  of  feeding  upon  humates, 
It  becomes  important  to  determine  to  what  extent  the  addition  of 
animal  and  vegetable  matters  to  the  soil  is  capable  of  affecting  the 
amount  of  available  plant  food. 
Experiments  conducted  at  the  Minnesota  Agricultural  Experiment 
Station  have  an  important  bearing  upon  this  question.  To  a  box 
holding  100  lbs.  of  loam  soil  20  lbs.  of  cow  manure  was  added.  The 
contents  pf  the  box  were  kept  moist  and  well  mixed.  At  the  end  of 
twelve  months  the  amount  of  mineral  matter  combined  with  the  hnmus 
was  determined,  and  the  amount  found  compared  with  that  originally 
in  the  box.  Another  box  containing  an  equal  amount  of  the  same  soil 
to  which  no  manure  was  added  was  treated  in  the  same  manner.  In  the 
first  case  the  mineral  matter  originally  present  in  the  manure  was 
deducted,  as  well  as  the  amount  which  was  only  soluble  in  the  solutions 
used  in  the  anjilysis.  The  results  were  as  follows  • 
Increase  op  Humates  in  the  Soil  due  to  Applications  op  Manure, 
Total  hu- 
niates  in 
too  pounds 
of  original 
soil. 
Total  at 
the  end  of 
12  months 
in  manured 
box. 
Gain  of 
humates 
from  soil 
through 
manure. 
Total  hu¬ 
mates  at 
the  end  of 
12  months, 
no  manure. 
T.OS8 
when  no 
manure 
was 
added. 
Grains. 
Grams. 
Grains. 
Grams, 
Grams. 
Potash 
7-25 
9-14 
1-89 
G-92 
0-.33 
Soda  , . 
7-.- 1 
10-11 
2  27 
7-50 
•34 
Iron . 
2-44 
4-i:i 
1-69 
2-46 
— 
Magnesia 
*j)5 
•5- 
•19 
•27 
•08 
Alumina 
2-96 
4-l)4 
1-08 
2-76 
•21 
Pliosphori  ’.  acid 
1107 
2-02 
11-50 
•47 
As  will  be  seen,  the  cow  manure  increased  the  amount  of  mineral 
matter  combined  with  the  humus  to  the  extent  of  15  to  25  per  cent,  of 
the  original  amount  present  in  the  soil.  In  addition  to  adding  new 
elements  of  fertility  to  the  soil,  it  has  also  resulted  in  changing  a  part 
of  the  Dotasb,  magnesia,  and  phosphoric  acid,  as  well  as  other  solid 
elements,  into  forms  more  valuable  as  plant  food.  The  manure,  there¬ 
fore  not  only  has  a  direct  fertilising  value,  but  is  also  useful  in  making 
the  inert  plant  food  of  the  soil  more  available.  A  number  of  facts  in 
field  practice  also  point  to  the  same  conclusion. 
It  is  well  known  that  barnyard  manure  is  among  the  most  laiting  in 
effect  of  any  of  the  fertilisers  which  can  be  applied.  This  is  undoubtedly 
due  to  the  power  which  the  manure  possesses  of  uniting  with  the  soil 
potash  and  phosphoric  acid  to  produce  humates. 
It  has  been  frequently  observed  that  when  Potatoes  are  cultivated 
on  new  prairie  land  for  three  or  four  years  in  succession,  both  the  yield 
and  the  size  of  the  Potatoes  decrease.  When  the  land  is  seeded  to  a  grass 
crop,  the  sod  ploughed  under,  and  Potatoes  again  planted,  the  yield  and 
size  of  the  Potatoes  are  often  nearly  the  same  as  when  the  land  was  new. 
This  result  lias  been  attained  without  the  addition  of  any  manure  to  the 
land  except  the  vegetable  matter  in  the  sod  which  has  furnished 
materials  for  the  formation  of  humates.  In  the  same  way,  Wheat  grown 
continuously  on  prairie  soil  will  gradually  decline  in  yield,  but  if  grass 
is  alternated  with  the  Wl\ca.t.  nearly  the  original  yields  are  restored. 
Besides  performing  the  useful  functions  just  discussed,  which  are 
essentially  chemical  in  character,  humus  profoundly  modifies  the 
physical  properties  of  soils.  This  influence  is  most  marked  in  relation 
to  the  water  content  and  temperature  of  the  soil . 
Humus  and  the  Water  Supply  op  Citops. 
A  Soil  rich  in  humus  not  only  absorbs  more  water,  but  holds  it  more 
tenaciously  in  time  of  drought  t^an  a  soil  poor  in  humus.  ^  In  fact,  this 
is  one  of  the  most  important  differences  between  soils  rich  in  humus  and 
those  poor  in  hnmus.  A  soil  which  by  long  cultivation  has  lost  half  of 
its  total  humus  will  show  a  loss  bf  10  to  25  per  cent,  of  its  water- 
holding  power.  These  differences  are  well  illustrated  in  the  following 
table,  compiled  from  data  obtained  in  the  examination  of  two  typical 
Minnesota  soils. 
Water  Capacity  op  Soils  Containing  Hifeeuent  Amounts  op  Humus. 
Water. 
In 
original 
soil. 
After  ten 
hours 
exposure 
to  the  sun. 
Loss. 
Soil  richer  in  humus  (3-75  per  cent.) 
Soil  poorer  in  humus  (2-50  per  cent.) 
per  cent. 
10-48 
12-14 
per  cent. 
6-12 
3-04 
per  cent. 
10-26 
8-20 
Humus  is  also  an  important  factor,  especially  in  sandy  soils,  in 
assisting  the  capillary  rise  of  subsoil  water  to  the  roots  of  crops.  In  a 
mixture  of  sand  and  humus  water  will  rise  to  the  surface  by  capillarity 
much  more  rapidly  than  in  pure  sand.  As  is  well  known,  soils  which 
are  properly  manured  and  thus  supplied  with  abundant  humus  retain 
more  water  and  yield  it  up  more  slowly  and  evenly  to  growing  crops 
than  unmannred  soils.  The  part  which  the  humus  takes  in  the  water 
supply  of  crops  is  sufficient  in  itself  for  placing  a  high  value  upon  the 
humus  of  the  soil. 
Humus  and  the  Heat  op  the  Soil. 
Humus  soils  are  generally  considered  cold  or  sour,  but  this  is  not 
always  true  of  them.  In  humus  soils  decomposition  or  oxidation  of  the 
organic  materials  is  constantly  taking  place,  and  this  oxidation  is  accom¬ 
panied  by  the  evolution  of  a  certain  amount  of  heat.  A  portion  of  this 
heat  is  used  up  in  warming  and  evaporating  the  additional  water  stored 
in  the  soil  on  account  of  the  humus,  but  even  after  this  is  provided 
