﻿94 
  DECIDUOUS 
  FEUIT 
  INSECTS 
  AND 
  INSECTICIDES. 
  

  

  hazelnut, 
  and 
  osage 
  orange. 
  In 
  addition 
  to 
  the 
  above 
  the 
  writer 
  has 
  

   observed 
  the 
  larvae 
  feeding 
  on 
  grape, 
  blackberry, 
  cottonwood, 
  Caro- 
  

   lina 
  poplar, 
  basswood, 
  cedar, 
  lilac, 
  Virginia 
  creeper, 
  snowball, 
  hop- 
  

   vines, 
  and 
  oats, 
  wheat, 
  alfalfa, 
  red 
  clover, 
  onions, 
  peas, 
  beans, 
  

   radishes, 
  and 
  rhubarb 
  that 
  were 
  growing 
  in 
  or 
  adjacent 
  to 
  badly 
  

   infested 
  orchards. 
  This 
  species 
  appears 
  to 
  be 
  able 
  to 
  thrive 
  on 
  the 
  

   foliage 
  of 
  almost 
  any 
  plant. 
  

  

  CHARACTER 
  OF 
  INJURY. 
  

  

  As 
  the 
  manner 
  in 
  which 
  the 
  larvae 
  attack 
  the 
  various 
  host 
  plants 
  

   differs 
  to 
  a 
  certain 
  degree, 
  it 
  seems 
  advisable 
  to 
  give 
  a 
  rather 
  full 
  dis- 
  

   cussion 
  of 
  the 
  more 
  important 
  injuries, 
  especially 
  those 
  occurring 
  on 
  

   fruit 
  trees. 
  

  

  In 
  the 
  spring, 
  just 
  as 
  the 
  buds 
  are 
  bursting, 
  the 
  larvae 
  begin 
  to 
  

   gnaw 
  their 
  way 
  out 
  of 
  the 
  eggshells 
  and 
  hard 
  protective 
  covering 
  of 
  

   the 
  egg 
  masses. 
  (PI. 
  XII, 
  fig. 
  1.) 
  The 
  young 
  caterpillars 
  at 
  once 
  

   migrate 
  to 
  the 
  developing 
  buds 
  and 
  begin 
  feeding 
  on 
  the 
  unfolding 
  

   leaves. 
  At 
  first 
  they 
  eat 
  small 
  inconspicuous 
  holes 
  in 
  the 
  unfolded 
  

   leaves, 
  and 
  at 
  this 
  time 
  the 
  average 
  orchardist 
  is 
  not 
  aware 
  of 
  their 
  

   presence. 
  After 
  feeding 
  in 
  this 
  manner 
  for 
  a 
  few 
  days 
  the 
  larvae 
  be- 
  

   come 
  quite 
  conspicuous 
  as 
  they 
  begin 
  to 
  spin 
  fine 
  silken 
  threads 
  from 
  

   leaf 
  to 
  leaf. 
  Eventually 
  they 
  fold 
  or 
  roll 
  up 
  a 
  single 
  leaf 
  or 
  a 
  cluster 
  

   of 
  leaves 
  and 
  here 
  they 
  feed 
  for 
  the 
  greater 
  part 
  of 
  the 
  time, 
  though 
  

   occasionally 
  straying 
  out 
  of 
  their 
  concealment 
  to 
  feed 
  in 
  the 
  open. 
  

   (PL 
  XIII, 
  fig. 
  1.) 
  Before 
  the 
  blossoms 
  are 
  fully 
  out, 
  or 
  even 
  before 
  

   the 
  cluster 
  buds 
  have 
  separated, 
  the 
  " 
  worms" 
  can 
  be 
  observed 
  

   webbing 
  them 
  together 
  and 
  feeding 
  voraciously. 
  Very 
  often 
  serious 
  

   injury 
  results 
  before 
  the 
  trees 
  come 
  into 
  blossom. 
  Later 
  in 
  the 
  

   season 
  the 
  webs 
  produced 
  by 
  the 
  larvae 
  are 
  often 
  quite 
  conspicuous, 
  

   as 
  is 
  shown 
  in 
  Plate 
  XV. 
  

  

  As 
  soon 
  as 
  the 
  young 
  fruit 
  has 
  set 
  the 
  larvae 
  cease 
  feeding 
  on 
  the 
  

   foliage 
  to 
  a 
  large 
  extent, 
  and 
  now 
  fasten 
  one 
  or 
  more 
  leaves 
  to 
  the 
  

   fruit 
  and 
  within 
  this 
  protection 
  feed 
  greedily, 
  at 
  first 
  eating 
  the 
  skin 
  

   only, 
  but 
  shortly 
  consuming 
  the 
  pulp 
  and 
  the 
  seeds 
  or 
  stone, 
  depend- 
  

   ing 
  on 
  the 
  kind 
  of 
  fruit 
  attacked. 
  (PL 
  XIII, 
  Hg. 
  2.) 
  Sometimes 
  

   young 
  apples 
  are 
  completely 
  devoured 
  except 
  for 
  the 
  stem 
  and 
  a 
  

   portion 
  of 
  the 
  calyx 
  end. 
  Cases 
  have 
  been 
  noticed 
  where 
  the 
  larvae 
  

   have 
  completely 
  gnawed 
  through 
  the 
  stems, 
  thus 
  causing 
  the 
  fruit 
  

   to 
  fall 
  to 
  the 
  ground 
  or 
  remain 
  suspended 
  within 
  the 
  feeding 
  nest. 
  

   Damage 
  done 
  to 
  apples 
  as 
  well 
  as 
  other 
  fruits 
  is 
  usually 
  so 
  severe 
  that 
  

   the 
  fruit 
  can 
  not 
  outgrow 
  the 
  injury, 
  thus 
  causing 
  a 
  large 
  percentage 
  

   of 
  unmerchantable 
  or 
  second-class 
  fruit 
  at 
  picking 
  time. 
  Much 
  fruit 
  

   is 
  also 
  caused 
  to 
  fall 
  prematurely 
  on 
  account 
  of 
  the 
  serious 
  injury 
  

   inflicted 
  on 
  it 
  when 
  young. 
  The 
  writer 
  has 
  seen 
  several 
  orchards 
  

  

  