﻿ARTIFICIAL 
  CONTROL. 
  43 
  

  

  careful, 
  clean 
  cultivation, 
  so 
  that 
  all 
  weeds 
  may 
  be 
  kept 
  down 
  in 
  

   the 
  fields 
  at 
  all 
  times, 
  including 
  the 
  spring 
  and 
  fall. 
  These 
  same 
  

   weeds, 
  especially 
  the 
  different 
  species 
  of 
  wild 
  lettuce, 
  should 
  be 
  care- 
  

   fully 
  destroyed 
  along 
  the 
  edges 
  of 
  all 
  fields 
  and 
  fence 
  corners 
  and 
  

   along 
  the 
  roads 
  and 
  railroad 
  tracks. 
  Cotton 
  and 
  beans 
  should 
  not 
  

   follow 
  in 
  old 
  alfalfa 
  fields 
  if 
  the 
  latter 
  were 
  badly 
  infested 
  with 
  the 
  

   bean 
  thrips, 
  and 
  fields 
  of 
  these 
  crops 
  should 
  be 
  removed 
  as 
  far 
  as 
  

   possible 
  from 
  the 
  alfalfa 
  fields. 
  They 
  should 
  also 
  be 
  planted 
  as 
  

   early 
  as 
  is 
  consistent 
  with 
  good 
  farming 
  and 
  encouraged 
  by 
  fre- 
  

   quent 
  cultivations 
  and 
  fertilizers 
  where 
  necessary 
  to 
  produce 
  an 
  early 
  

   crop 
  so 
  as 
  to 
  escape 
  the 
  ravages 
  of 
  the 
  bean 
  thrips 
  in 
  the 
  late 
  summer. 
  

  

  As 
  this 
  insect 
  feeds 
  on 
  such 
  a 
  variety 
  of 
  plants 
  it 
  is 
  hardly 
  pos- 
  

   sible 
  that 
  rotation 
  of 
  crops 
  would 
  aid 
  materially 
  in 
  its 
  control 
  unless 
  

   some 
  crop 
  could 
  be 
  found 
  that 
  is 
  quite 
  immune. 
  

  

  Where 
  it 
  is 
  injuring 
  alfalfa 
  Mr. 
  Wildermuth 
  recommends 
  disking 
  

   and 
  thorough 
  renovation 
  of 
  the 
  fields 
  and 
  good 
  irrigation 
  in 
  order 
  

   to 
  give 
  the 
  plants 
  as 
  much 
  chance 
  as 
  possible 
  to 
  make 
  a 
  quick 
  growth. 
  

  

  SPRAYING. 
  

  

  The 
  control 
  of 
  this 
  thrips 
  by 
  spraying 
  is 
  impracticable 
  for 
  a 
  crop 
  

   such 
  as 
  alfalfa 
  or 
  cotton, 
  and 
  because 
  of 
  the 
  low 
  trailing 
  vines 
  of 
  

   the 
  bean 
  will 
  probably 
  be 
  successful 
  with 
  this 
  plant 
  only 
  when 
  the 
  

   vines 
  can 
  be 
  easily 
  reached 
  from 
  the 
  underside. 
  In 
  case 
  injury 
  to 
  

   fruit 
  trees 
  is 
  threatened 
  it 
  can 
  be 
  controlled 
  by 
  using 
  the 
  spray 
  so 
  

   successful 
  against 
  the 
  pear 
  thrips. 
  This 
  is 
  a 
  solution 
  of 
  2f 
  per 
  cent 
  

   nicotine, 
  diluted 
  at 
  the 
  rate 
  of 
  1 
  part 
  to 
  GO 
  parts 
  of 
  water 
  in 
  a 
  6 
  

   per 
  cent 
  distillate-oil 
  emulsion. 
  1 
  

  

  The 
  distillate-oil 
  stock 
  emulsion, 
  according 
  to 
  the 
  formula 
  of 
  

   Foster 
  and 
  Jones, 
  is 
  made 
  as 
  follows: 
  

  

  Hot 
  water 
  gallons__ 
  12 
  

  

  Fish-oil 
  or 
  whale-oil 
  soap 
  pounds— 
  80 
  

  

  Distillate-oil 
  (raw) 
  30° 
  to 
  34° 
  Baumo 
  gallons__ 
  20 
  

  

  * 
  

  

  Have 
  the 
  water 
  boiling 
  hot 
  when 
  put 
  into 
  the 
  spray 
  tank 
  and 
  add 
  the 
  soap 
  

   immediately 
  while 
  the 
  agitator 
  is 
  running 
  at 
  a 
  good 
  speed. 
  "When 
  the 
  soap 
  is 
  

   all 
  thoroughly 
  dissolved 
  pour 
  in 
  the 
  oil 
  slowly, 
  keeping 
  the 
  mixture 
  well 
  agi- 
  

   tated 
  while 
  the 
  oil 
  is 
  going 
  into 
  the 
  tank. 
  When 
  all 
  of 
  the 
  oil 
  is 
  in 
  and 
  well 
  

   mixed, 
  pump 
  out 
  through 
  the 
  nozzles 
  at 
  good 
  pressure 
  (not 
  less 
  than 
  175 
  

   pounds) 
  into 
  storage 
  tanks. 
  

  

  No 
  one 
  should 
  attempt 
  to 
  make 
  this 
  stock 
  emulsion 
  without 
  a 
  power 
  spraying 
  

   machine, 
  as 
  thorough 
  agitation 
  and 
  high 
  pressure 
  are 
  important 
  requisites. 
  

   Also, 
  care 
  should 
  be 
  used 
  in 
  having 
  measurements 
  reasonably 
  exact, 
  the 
  water 
  

   hoping 
  hot. 
  and 
  the 
  soap 
  thoroughly 
  dissolved 
  before 
  any 
  oil 
  is 
  put 
  in. 
  This 
  

   siock 
  solution 
  contains 
  approximately 
  55 
  per 
  cent 
  oil, 
  and 
  to 
  make 
  a 
  3 
  per 
  cent 
  

   emulsion 
  use 
  5* 
  gallons 
  of 
  this 
  stock 
  in 
  each 
  100-gallon 
  tank. 
  

  

  l 
  For 
  :i 
  full 
  account 
  of 
  this 
  spray 
  ;is 
  used 
  ;uc:iinsf 
  the 
  pear 
  thrips, 
  sir 
  Circular 
  I'll, 
  

   Huroau 
  of 
  Entomology, 
  U. 
  S. 
  Dcpt. 
  of 
  Agriculture, 
  pp. 
  8-9. 
  

  

  