﻿ORCHARD 
  INSECTS 
  PACIFIC 
  NORTHWEST 
  

  

  13 
  

  

  plied 
  for 
  control 
  of 
  the 
  codling 
  

   moth, 
  or 
  they 
  may 
  be 
  used 
  alone. 
  

   The 
  concentration 
  of 
  the 
  acaricide, 
  

   or 
  mite-killing 
  material, 
  should 
  be 
  

   as 
  follows 
  for 
  100 
  gallons 
  of 
  spray 
  : 
  

  

  Parathion 
  (15 
  -percent 
  

   wettable 
  powder 
  or 
  

  

  equivalent) 
  ^/4 
  to 
  1 
  pound 
  

  

  Rotenone 
  : 
  

  

  1- 
  or 
  1.5-percent 
  

  

  liquid 
  1 
  pint 
  

  

  plus 
  summer- 
  

   oil 
  emulsion. 
  2 
  quarts 
  

   (or) 
  1- 
  or 
  1.5-percent 
  

   wettable 
  

  

  powder 
  1 
  pound 
  

  

  plus 
  summer- 
  

   oil 
  emulsion_ 
  2 
  quarts 
  

  

  These 
  quantities 
  may 
  be 
  increased 
  

   when 
  used 
  in 
  air-carrier 
  machines. 
  

   Other 
  acaricides, 
  such 
  as 
  the 
  di- 
  

   cyclohexylamine 
  salt 
  of 
  dinitro-6>- 
  

   cyclo 
  hexyl 
  phenol 
  and 
  tetraethyl 
  

   pyrophosphate, 
  may 
  be 
  employed 
  

   advantageously, 
  and 
  the 
  manufac- 
  

   turer's 
  directions 
  should 
  be 
  fol- 
  

   lowed 
  carefully. 
  Toxaphene 
  (50- 
  

   percent 
  emulsible 
  material 
  or 
  its 
  

   equivalent), 
  1 
  to 
  li/^ 
  pints 
  to 
  100 
  

   gallons 
  of 
  spray, 
  is 
  also 
  effective 
  

   when 
  added 
  to 
  DDT 
  applied 
  for 
  

   control 
  of 
  the 
  codling 
  moth. 
  

  

  Some 
  of 
  these 
  acaricides 
  are 
  

   available 
  as 
  dusts. 
  If 
  used 
  in 
  this 
  

   form, 
  the 
  quantity 
  of 
  active 
  in- 
  

   gredient 
  applied 
  per 
  tree 
  should 
  be 
  

   the 
  same 
  as 
  when 
  the 
  material 
  is 
  

   applied 
  as 
  a 
  spray. 
  Most 
  acari- 
  

   cides 
  are 
  effective 
  for 
  3 
  weeks 
  or 
  a 
  

   month 
  when 
  used 
  as 
  sprays, 
  and 
  

   for 
  a 
  shorter 
  time 
  when 
  used 
  as 
  

   dusts. 
  Therefore, 
  it 
  will 
  be 
  neces- 
  

   sary 
  to 
  repeat 
  the 
  applications 
  at 
  

   such 
  intervals. 
  The 
  final 
  applica- 
  

   tion 
  should 
  be 
  made 
  at 
  least 
  30 
  

   days 
  before 
  harvest 
  to 
  avoid 
  hav- 
  

   ing 
  excessive 
  residues 
  on 
  the 
  fruit 
  

   at 
  that 
  time. 
  

  

  Caution. 
  — 
  Extreme 
  caution 
  must 
  be 
  

   used 
  in 
  handling, 
  storing, 
  and 
  applying 
  

   parathion 
  and 
  tetraethyl 
  pyrophosphate. 
  

   (See 
  p. 
  59, 
  for 
  details.) 
  

  

  Summer 
  spraying 
  or 
  dusting 
  for 
  

   orchard 
  mites 
  must 
  be 
  thorough, 
  

   as 
  the 
  mites 
  infest 
  the 
  entire 
  tree. 
  

  

  and 
  portions 
  not 
  covered 
  often 
  

   harbor 
  enough 
  mites 
  to 
  reinfest 
  

   the 
  tree 
  in 
  a 
  short 
  time. 
  

  

  Pear 
  Leaf 
  Blister 
  Mite 
  

  

  The 
  pear 
  leaf 
  blister 
  mite 
  lives 
  

   in 
  the 
  buds, 
  foliage, 
  and 
  fruit 
  of 
  

   apple 
  and 
  pear 
  trees. 
  It 
  produces 
  

   small 
  galls 
  or 
  blisters 
  on 
  the 
  leaves. 
  

   At 
  first 
  these 
  galls 
  are 
  greenish 
  or 
  

   reddish, 
  but 
  later 
  they 
  turn 
  brown 
  

   and 
  cause 
  dead 
  areas. 
  These 
  areas 
  

   may 
  be 
  distinguished 
  from 
  apple 
  

   scab 
  by 
  the 
  small 
  round 
  holes 
  on 
  

   the 
  under 
  surface 
  of 
  the 
  leaf 
  ap- 
  

   proximately 
  in 
  the 
  center 
  of 
  each 
  

   blister 
  (fig. 
  15, 
  A). 
  

  

  Figure 
  15. 
  — 
  Pear 
  leaf 
  blister 
  mite: 
  A, 
  In- 
  

   festation 
  on 
  an 
  apple 
  leaf; 
  B, 
  deformed 
  

   and 
  russeted 
  apple; 
  C, 
  adult 
  mites. 
  

  

  