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  THE 
  BEAN 
  THKIPS. 
  

  

  On 
  September 
  18, 
  1911, 
  he 
  wrote 
  : 
  

  

  This 
  tlirips 
  is 
  very 
  abundant 
  in 
  alfalfa 
  fields 
  at 
  this 
  time 
  of 
  year, 
  the 
  larvae 
  

   being 
  present 
  on 
  the 
  older 
  alfalfa 
  and 
  the 
  adults 
  present 
  on 
  the 
  younger 
  shoots 
  

   and 
  leaves. 
  Many 
  leaves, 
  after 
  being 
  badly 
  scarred 
  by 
  the 
  thrips, 
  wilt 
  and 
  fall 
  

   off, 
  so 
  that 
  the 
  damage 
  is 
  soon 
  very 
  great. 
  It 
  seems 
  rather 
  strauge 
  that 
  this 
  

   thrips 
  should 
  become 
  so 
  very 
  abundant 
  in 
  the 
  fall 
  of 
  the 
  year 
  and 
  Euthripa 
  

   tritici, 
  the 
  other 
  important 
  alfalfa 
  thrips, 
  should 
  decrease 
  in 
  numbers 
  and 
  

   that 
  in 
  the 
  spring 
  of 
  the 
  year 
  just 
  the 
  opposite 
  should 
  be 
  the 
  case. 
  

  

  COTTON. 
  

  

  September 
  22, 
  1910, 
  Mr. 
  Wildermuth 
  wrote 
  : 
  

  

  This 
  thrips 
  was 
  found 
  damaging 
  cotton 
  about 
  11 
  miles 
  southeast 
  of 
  El 
  

   Centro, 
  Cal. 
  The 
  cotton 
  was 
  only 
  damaged 
  in 
  one 
  corner 
  of 
  the 
  field, 
  and 
  it 
  

   happens 
  that 
  fresh 
  alfalfa 
  is 
  being 
  stacked 
  close 
  to 
  this 
  corner. 
  

  

  September 
  28 
  a 
  field 
  of 
  cotton 
  east 
  of 
  Imperial 
  had 
  a 
  strip 
  through 
  the 
  center 
  

   of 
  the 
  field 
  damaged 
  by 
  this 
  thrips. 
  September 
  30 
  numerous 
  fields 
  on 
  the 
  east 
  

   side 
  of 
  the 
  valley 
  were 
  being 
  damaged 
  by 
  this 
  pest. 
  The 
  leaves 
  were 
  dead 
  and 
  

   rusty 
  looking 
  and 
  the 
  plants 
  in 
  bad 
  condition. 
  The 
  damage 
  was 
  not 
  as 
  great 
  as 
  

   if 
  the 
  work 
  had 
  begun 
  earlier 
  in 
  the 
  season, 
  but 
  was 
  at 
  that 
  time 
  very 
  great. 
  

  

  October 
  11 
  several 
  cotton 
  fields 
  at 
  Holtville, 
  on 
  the 
  east 
  side 
  of 
  the 
  valley, 
  

   were 
  examined. 
  A 
  great 
  many 
  fields 
  showed 
  considerable 
  injury. 
  The 
  leaves 
  

   were 
  eaten 
  and 
  turned 
  a 
  sickly 
  yellowish 
  or 
  brown, 
  many 
  often 
  being 
  curled. 
  

   A 
  field 
  on 
  the 
  Young 
  ranch 
  was 
  as 
  badly 
  damaged 
  as 
  any 
  seen, 
  and 
  this 
  field 
  

   lay 
  alongside 
  an 
  alfalfa 
  field. 
  Three 
  other 
  fields 
  on 
  the 
  same 
  ranch 
  showed 
  

   very 
  little 
  damage. 
  The 
  former 
  field 
  was 
  of 
  a 
  late 
  planting. 
  This 
  thrips 
  has 
  

   caused 
  much 
  more 
  damage 
  to 
  cotton 
  than 
  was 
  anticipated, 
  and 
  if 
  it 
  should 
  

   begin 
  its 
  work 
  early 
  in 
  the 
  season 
  it 
  might 
  prove 
  extremely 
  destructive. 
  Be- 
  

   cause 
  of 
  this, 
  as 
  well 
  as 
  other 
  still 
  better 
  reasons, 
  cotton 
  should 
  be 
  planted 
  as 
  

   early 
  as 
  possible 
  in 
  the 
  spring. 
  

  

  In 
  November, 
  1911, 
  Mr. 
  Wildermuth 
  wrote 
  : 
  

  

  Mr. 
  Packard 
  and 
  cotton 
  growers 
  throughout 
  the 
  valley 
  report 
  but 
  little 
  injury 
  

   to 
  cotton 
  by 
  this 
  thrips 
  this 
  year. 
  I 
  found 
  only 
  two 
  specimens 
  of 
  larvae 
  myself, 
  

   and 
  a 
  few 
  adults. 
  It 
  would 
  seem 
  as 
  if 
  the 
  damage 
  to 
  cotton 
  comes 
  when 
  cotton 
  

   follows 
  alfalfa. 
  This 
  year, 
  there 
  beiflg 
  but 
  little 
  alfalfa 
  land 
  put 
  ^o 
  cotton 
  

   and 
  more 
  cotton 
  following 
  cotton, 
  the 
  damage 
  was 
  not 
  so 
  noticeable. 
  

  

  WILD 
  PLANTS. 
  

  

  Of 
  all 
  food 
  plants 
  of 
  this 
  insect 
  the 
  wild 
  spiny 
  lettuce 
  (Lactuca 
  

   scariola) 
  seems 
  to 
  be 
  preferred, 
  at 
  least 
  in 
  the 
  vicinity 
  of 
  Los 
  Angeles. 
  

   From 
  early 
  spring, 
  when 
  this 
  plant 
  comes 
  up, 
  until 
  it 
  dies 
  down 
  in 
  

   the 
  fall, 
  it 
  is 
  usually 
  badly 
  infested 
  by 
  thrips. 
  Many 
  cases 
  have 
  been 
  

   observed 
  where 
  other 
  food 
  plants, 
  such 
  as 
  beans, 
  etc., 
  in 
  the 
  same 
  field 
  

   were 
  only 
  slightly 
  infested, 
  while 
  the 
  spiny 
  lettuce 
  near 
  by 
  was 
  so 
  

   badly 
  attacked 
  that 
  many 
  plants 
  were 
  dead. 
  Furthermore, 
  this 
  weed 
  

   is 
  one 
  of 
  the 
  commonest 
  in 
  the 
  country, 
  occurring 
  abundantly 
  in 
  un- 
  

   cultivated 
  or 
  even 
  in 
  badly 
  cultivated 
  fields. 
  In 
  addition 
  it 
  grows 
  

   up 
  in 
  dense 
  clumps 
  in 
  all 
  fence 
  rows 
  and 
  roadsides, 
  and 
  the 
  rights 
  

   of 
  way 
  of 
  the 
  different 
  railroads 
  are 
  densely 
  packed 
  by 
  this 
  plant. 
  

  

  