﻿ORCHARD 
  INSECTS 
  PACIFIC 
  NORTHWEST 
  

  

  37 
  

  

  foliation 
  may 
  occur 
  in 
  nonirri- 
  

   gated 
  orchards, 
  frequently 
  accom- 
  

   panied 
  by 
  the 
  dropping 
  of 
  some 
  of 
  

   the 
  fruit. 
  Injury 
  by 
  the 
  mites 
  

   may 
  prevent 
  the 
  fruit 
  buds 
  from 
  

   forming, 
  or 
  at 
  least 
  may 
  weaken 
  

   them, 
  causing 
  a 
  small 
  crop 
  or 
  small 
  

   fruit 
  the 
  following 
  year. 
  This 
  

   injury 
  is 
  often 
  much 
  more 
  serious 
  

   than 
  is 
  apparent. 
  The 
  species 
  

   most 
  commonly 
  found 
  on 
  these 
  

   trees 
  are 
  the 
  clover 
  mite, 
  the 
  Euro- 
  

   pean 
  red 
  mite, 
  and 
  the 
  Pacific 
  mite. 
  

  

  CONTROL 
  

  

  Control 
  of 
  orchard 
  mites 
  on 
  

   prune 
  and 
  plum 
  trees 
  is 
  similar 
  to 
  

   that 
  on 
  apple 
  (p. 
  12) 
  and 
  peach 
  

   trees 
  (p. 
  45) 
  . 
  If 
  it 
  is 
  necessary 
  to 
  

   use 
  sulfur 
  sprays 
  for 
  controlling 
  

   brown 
  rot, 
  special 
  applications 
  

   against 
  orchard 
  mites 
  should 
  not 
  

   be 
  needed. 
  

  

  Apple 
  Rust 
  Mite 
  

  

  The 
  apple 
  rust 
  mite 
  causes 
  prune 
  

   leaves 
  to 
  curl 
  longitudinally 
  and 
  

   become 
  russeted 
  or 
  silvered. 
  The 
  

   fruit 
  may 
  also 
  be 
  russeted. 
  Con- 
  

   trol 
  is 
  the 
  same 
  on 
  prune 
  trees 
  as 
  

   on 
  apple 
  and 
  pear 
  trees 
  (p. 
  14) 
  . 
  

  

  Leafhoppers 
  

  

  Leafhoppers 
  often 
  become 
  nu- 
  

   merous 
  on 
  prune 
  trees. 
  A 
  species 
  

   found 
  in 
  the 
  Yakima 
  Valley, 
  

   Typhlocyha 
  prunicola 
  Edw., 
  and 
  

   the 
  rase 
  leafhopper 
  may 
  be 
  con- 
  

   trolled 
  on 
  prune 
  trees 
  in 
  the 
  same 
  

   manner 
  as 
  on 
  apple 
  trees 
  (p. 
  24). 
  

   The 
  materials 
  mentioned 
  for 
  

   orchard 
  mites 
  (p. 
  12) 
  will 
  also 
  

   control 
  leafhoppers. 
  

  

  Peach 
  Tree 
  Borers 
  

  

  The 
  peach 
  tree 
  borer 
  and 
  the 
  

   western 
  variety 
  of 
  the 
  same 
  species 
  

   are 
  both 
  found 
  in 
  the 
  Pacific 
  

   Northwest. 
  These 
  borers 
  are 
  seri- 
  

   ous 
  pests 
  of 
  prune 
  and 
  peach 
  trees, 
  

   as 
  w^ell 
  as 
  of 
  apricots 
  and 
  plums 
  

   and 
  occasionally 
  cherries. 
  The 
  

   injury 
  occurs 
  chiefly 
  in 
  the 
  crown 
  

  

  and 
  roots 
  of 
  the 
  trees, 
  where 
  the 
  

   borers 
  tunnel 
  beneath 
  the 
  surface, 
  

   feeding 
  on 
  the 
  inner 
  or 
  growing 
  

   layer 
  of 
  bark 
  Young 
  trees 
  may 
  be 
  

   completely 
  girdled 
  and 
  killed 
  (fig. 
  

   44) 
  , 
  and 
  older 
  trees 
  are 
  frequently 
  

   so 
  weakened 
  that 
  they 
  become 
  sub- 
  

   ject 
  to 
  other 
  insect 
  pests 
  or 
  to 
  dis- 
  

   eases. 
  The 
  presence 
  of 
  borers 
  in 
  

   the 
  trees 
  is 
  often 
  first 
  indicated 
  by 
  

   a 
  quantity 
  of 
  gum 
  at 
  the 
  base 
  of 
  

   the 
  trunk, 
  mixed 
  with 
  dirt 
  and 
  

   f 
  rass. 
  Poor 
  condition 
  of 
  the 
  trees 
  

   may 
  also 
  indicate 
  that 
  the 
  borers 
  

   are 
  present. 
  Trees 
  should 
  be 
  ex- 
  

   amined 
  periodically 
  for 
  borers, 
  es- 
  

  

  Figure 
  4:4. 
  — 
  Base 
  of 
  young 
  peach 
  tree 
  

   severely 
  injured 
  by 
  peach 
  borers. 
  

  

  pecially 
  if 
  they 
  are 
  not 
  making 
  

   good 
  growth 
  or 
  do 
  not 
  appear 
  to 
  

   be 
  thrifty. 
  The 
  borers 
  are 
  most 
  

   commonly 
  found 
  west 
  of 
  the 
  Cas- 
  

   cade 
  Mountains, 
  but 
  sometimes 
  

   become 
  injurious 
  elsewhere. 
  

  

  LIFE 
  history 
  

  

  The 
  adult 
  is 
  a 
  steel-blue 
  moth 
  

   with 
  a 
  wing 
  expanse 
  of 
  more 
  than 
  

   an 
  inch. 
  The 
  wings 
  of 
  the 
  male 
  

   moth 
  are 
  clear, 
  except 
  for 
  the 
  mar- 
  

   gins, 
  but 
  the 
  forewings 
  of 
  the 
  fe- 
  

   male 
  are 
  opaque. 
  The 
  female 
  of 
  

   the 
  eastern 
  form 
  has 
  an 
  orange 
  

   band 
  about 
  the 
  abdomen, 
  whereas 
  

   the 
  whole 
  abdomen 
  of 
  the 
  western 
  

   variety 
  is 
  steely 
  blue. 
  The 
  male 
  

  

  