﻿PLANT 
  BREEDING 
  179 
  

  

  When 
  thoroughly 
  dry, 
  the 
  product 
  of 
  each 
  plant 
  is 
  weighed, 
  

   and 
  only 
  a 
  few 
  of 
  the 
  heaviest 
  groups 
  of 
  heads 
  are 
  kept 
  for 
  seed. 
  

  

  2. 
  The 
  second 
  year 
  about 
  a 
  hundred 
  of 
  the 
  seeds 
  of 
  each 
  

   mother 
  plant 
  are 
  planted 
  in 
  a 
  group 
  (hundred-group 
  or 
  cent- 
  

   gener). 
  To 
  each 
  such 
  group 
  is 
  given 
  a 
  special 
  designating 
  

   number. 
  Heads 
  of 
  several 
  of 
  the 
  best 
  plants 
  in 
  each 
  hundred- 
  

   group 
  are 
  reserved 
  for 
  seed. 
  The 
  total 
  produced 
  by 
  each 
  

   hundred-group 
  is 
  weighed. 
  This 
  enables 
  the 
  experimenter 
  to 
  

   estimate 
  the 
  comparative 
  value 
  of 
  the 
  mother 
  plants. 
  

  

  3. 
  The 
  third 
  year 
  the 
  process 
  of 
  the 
  second 
  year 
  is 
  repeated. 
  

  

  4. 
  The 
  fourth 
  year 
  the 
  same 
  process 
  is 
  repeated. 
  

  

  5. 
  The 
  fifth 
  year 
  the 
  most 
  promising 
  varieties 
  are 
  planted 
  

   in 
  small 
  fields 
  in 
  the 
  ordinary 
  way. 
  Those 
  varieties 
  which 
  yield 
  

   abundantly 
  in 
  the 
  field 
  and 
  turn 
  out 
  well 
  in 
  the 
  milling 
  tests 
  

   which 
  are 
  applied 
  to 
  the 
  harvested 
  grain, 
  are 
  distributed 
  among 
  

   farmers 
  for 
  seed 
  wheat. 
  

  

  A 
  new 
  variety 
  can 
  soon 
  be 
  introduced 
  over 
  an 
  immense 
  

   territory. 
  It 
  is 
  estimated 
  that 
  in 
  fifteen 
  years 
  from 
  the 
  time 
  

   of 
  planting 
  one 
  seed 
  its 
  descendants 
  might 
  be 
  made 
  to 
  cover 
  

   more 
  than 
  5,000,000 
  acres 
  of 
  wheat 
  fields. 
  

  

  Wheat 
  breeding 
  is 
  still 
  making 
  such 
  rapid 
  progress 
  that 
  at 
  

   present 
  it 
  is 
  not 
  possible 
  to 
  say 
  how 
  much 
  the 
  quality 
  and 
  

   quantity 
  of 
  our 
  wheat 
  crop 
  may 
  yet 
  be 
  improved 
  by 
  the 
  in- 
  

   troduction 
  of 
  better 
  varieties. 
  The 
  total 
  number 
  of 
  acres 
  in 
  

   the 
  United 
  States 
  differs 
  considerably 
  from 
  year 
  to 
  year. 
  It 
  

   seems 
  likely, 
  as 
  a 
  rule, 
  to 
  exceed 
  45,000,000.* 
  The 
  average 
  

   yield 
  ranges 
  between 
  10 
  and 
  15 
  bushels 
  per 
  acre, 
  although 
  it 
  is 
  

   possible, 
  with 
  the 
  most 
  improved 
  seed 
  on 
  the 
  best 
  soils, 
  to 
  raise 
  

   more 
  than 
  40 
  bushels 
  per 
  acre. 
  2 
  Choice 
  of 
  the 
  best 
  seed 
  would 
  

   undoubtedly 
  increase 
  the 
  average 
  yield 
  5 
  or 
  more 
  bushels 
  

   per 
  acre. 
  It 
  is 
  easy 
  to 
  see 
  how 
  important 
  a 
  gain 
  this 
  would 
  be 
  

   if 
  it 
  were 
  calculated 
  in 
  terms 
  of 
  the 
  current 
  price 
  of 
  wheat. 
  

  

  1 
  See 
  Carleton, 
  " 
  The 
  Future 
  Wheat 
  Supply 
  of 
  the 
  United 
  States," 
  

   Science, 
  August 
  5, 
  1910. 
  

  

  2 
  See 
  Hopkins, 
  Soil 
  Fertility 
  and 
  Permanent 
  Agriculture. 
  Ginn 
  and 
  

   Company, 
  Boston. 
  

  

  