﻿WEED 
  SEEDS 
  AS 
  EOOD. 
  19 
  

  

  in 
  itself 
  to 
  prevent 
  practically 
  all 
  of 
  the 
  damage 
  to 
  grain 
  crops 
  by 
  the 
  

   horned 
  larks. 
  

  

  Finally, 
  it 
  ma} 
  r 
  be 
  said 
  in 
  the 
  bird's 
  favor 
  that 
  at 
  the 
  worst 
  the 
  

   damage 
  to 
  grain 
  from 
  the 
  horned 
  lark 
  is 
  not 
  great, 
  and 
  that 
  it 
  is 
  

   more 
  than 
  counterbalanced 
  by 
  the 
  good 
  done 
  through 
  the 
  destruc- 
  

   tion 
  of 
  harmful 
  insects 
  and 
  the 
  seeds 
  of 
  injurious 
  weeds. 
  

  

  Weeds. 
  

  

  The 
  plants 
  commonly 
  known 
  as 
  weeds, 
  from 
  their 
  injurious 
  effect 
  

   upon 
  agriculture, 
  are 
  more 
  important 
  than 
  any 
  of 
  the 
  other 
  enemies 
  

   of 
  the 
  farmer. 
  They 
  rob 
  the 
  soil 
  of 
  its 
  nutritive 
  elements 
  and 
  of 
  its 
  

   moisture, 
  and 
  thus 
  reduce 
  the 
  size 
  of 
  crops. 
  They 
  are 
  mostly 
  hardy, 
  

   vigorous 
  plants, 
  and 
  shade 
  and 
  choke 
  out 
  the 
  more 
  delicate 
  plants 
  of 
  cul- 
  

   tivation. 
  Many 
  fungous 
  diseases 
  of 
  cereal, 
  fruit, 
  and 
  other 
  crops, 
  such 
  

   as 
  rusts 
  and 
  rots, 
  depend 
  for 
  their 
  continuance 
  upon 
  weeds 
  as 
  interme- 
  

   diate 
  hosts. 
  Such 
  weeds 
  as 
  the 
  mustards 
  are 
  especially 
  well 
  known 
  as 
  

   the 
  primary 
  hosts 
  of 
  rusts. 
  Some 
  weeds 
  poison 
  stock; 
  the 
  spiny 
  seeds 
  

   or 
  burs 
  of 
  others 
  lessen 
  the 
  value 
  of 
  wool, 
  besides 
  being 
  the 
  cause 
  of 
  

   annoyance 
  to 
  all 
  animals 
  on 
  the 
  farm 
  and 
  to 
  man. 
  In 
  these 
  and 
  in 
  a 
  

   thousand 
  other 
  ways 
  weeds 
  injure 
  the 
  farmer. 
  They 
  are 
  present 
  

   everywhere, 
  and 
  their 
  numbers 
  are 
  limited 
  only 
  by 
  the 
  capacity 
  of 
  the 
  

   soil 
  and 
  the 
  extent 
  of 
  available 
  space. 
  Passing 
  to 
  particular 
  examples 
  

   of 
  their 
  fecundity, 
  we 
  may 
  mention 
  that 
  a 
  single 
  plant 
  of 
  foxtail 
  

   (Plate 
  II, 
  fig. 
  A), 
  the 
  seeds 
  of 
  which 
  were 
  eaten 
  by 
  nearly 
  350 
  of 
  the 
  

   horned 
  larks 
  examined, 
  has 
  been 
  known 
  to 
  produce 
  113,000 
  seeds, 
  and 
  

   a 
  plant 
  of 
  red 
  root 
  (tumbleweed), 
  the 
  seeds 
  of 
  which 
  are 
  the 
  food 
  next 
  

   preferred, 
  has 
  produced 
  115,000 
  seeds. 
  Such 
  reproductive 
  powers 
  if 
  

   unchecked 
  would 
  result 
  soon 
  in 
  covering 
  the 
  entire 
  surface 
  of 
  the 
  

   earth 
  with 
  weeds. 
  Even 
  as 
  it 
  is, 
  the 
  surface 
  soil 
  contains 
  so 
  many 
  

   seeds 
  that 
  they 
  often 
  seem 
  to 
  constitute 
  a 
  considerable 
  percentage 
  of 
  

   its 
  bulk. 
  At 
  Ames, 
  Iowa, 
  a 
  square 
  rod 
  of 
  ground 
  in 
  a 
  garden, 
  which 
  

   had 
  been 
  in 
  potatoes 
  the 
  jqrt 
  before 
  and 
  cultivated 
  with 
  a 
  hoe, 
  

   yielded 
  187,884 
  plants 
  of 
  .eight 
  common 
  weeds." 
  Crab 
  grass 
  and 
  its 
  

   allies, 
  which 
  are 
  great 
  pests 
  in 
  permanent 
  lawns, 
  and 
  the 
  seeds 
  of 
  

   which 
  are 
  eaten 
  freely 
  by 
  the 
  horned 
  larks, 
  occur 
  in 
  even 
  greater 
  

   number. 
  Professor 
  Beal 
  states 
  that 
  each 
  square 
  quarter 
  of 
  an 
  inch 
  in 
  

   his 
  garden 
  in 
  Maryland, 
  when 
  first 
  cultivated 
  in 
  the 
  spring, 
  contained 
  

   at 
  least 
  one 
  plant 
  of 
  crab 
  grass. 
  Upon 
  this 
  basis 
  the 
  number 
  of 
  plants 
  

   to 
  a 
  square 
  rod 
  is 
  627,26-1. 
  Three 
  times 
  the 
  weeds 
  were 
  cut 
  off, 
  but 
  

   each 
  time 
  they 
  appeared 
  in 
  as 
  great 
  numbers 
  as 
  before. 
  

  

  The 
  above 
  statements 
  indicate 
  the 
  vast 
  numbers 
  of 
  weeds 
  on 
  farms, 
  

   and 
  show 
  that 
  to 
  prevent 
  them 
  from 
  possessing 
  the 
  land 
  they 
  must 
  be 
  

   destroyed 
  in 
  all 
  stages 
  of 
  growth. 
  The 
  damage 
  they 
  cause, 
  reckoned 
  

  

  a 
  Bulletin 
  No. 
  70, 
  Exp. 
  Sta., 
  la. 
  State 
  College, 
  p. 
  465, 
  1903. 
  

  

  