﻿11 
  

  

  Woodlots 
  and 
  orchards 
  are 
  frequently 
  seen 
  in 
  which 
  the 
  trees 
  are 
  

   dying 
  from 
  defoliation 
  repeated 
  for 
  several 
  years. 
  

  

  According 
  to 
  Mr. 
  Surface, 
  this 
  defoliation 
  is 
  the 
  work 
  of 
  the 
  spring 
  

   cankerworm/ 
  and 
  he 
  has 
  published 
  some 
  notes 
  upon 
  the 
  methods 
  of 
  

   control. 
  When 
  the 
  advisability 
  of 
  planting 
  any 
  land 
  in 
  these 
  coun- 
  

   ties 
  with 
  forest 
  trees 
  is 
  contemplated, 
  this 
  factor 
  of 
  insect 
  damage 
  

   must 
  be 
  considered 
  carefully. 
  Methods 
  of 
  control 
  such 
  as 
  are 
  com- 
  

   monly 
  used 
  in 
  orchards 
  will 
  not 
  usually 
  be 
  practicable 
  in 
  a 
  forest 
  plan- 
  

   tation. 
  The 
  presence 
  of 
  this 
  insect 
  does 
  not 
  necessarily 
  prevent 
  for- 
  

   est 
  planting, 
  but 
  requires, 
  rather, 
  a 
  change 
  in 
  the 
  local 
  planting 
  site 
  

   or 
  a 
  postponement 
  of 
  planting 
  until 
  the 
  pest 
  has 
  been 
  reduced 
  in 
  num- 
  

   bers 
  by 
  its 
  natural 
  enemies 
  or 
  other 
  agencies. 
  

  

  INSECT 
  DAMAGE 
  TO 
  THE 
  LOCUST. 
  

  

  The 
  locust 
  (Robinia 
  pseudacacia) 
  , 
  because 
  of 
  its 
  rapid 
  growth, 
  its 
  

   adaptability 
  to 
  different 
  soil 
  conditions, 
  and 
  its 
  value 
  for 
  posts 
  and 
  

   pit 
  props, 
  is 
  a 
  valuable 
  tree 
  for 
  forest 
  planting. 
  Injuries 
  by 
  certain 
  

   insects, 
  however, 
  present 
  a 
  great 
  obstacle 
  to 
  its 
  use. 
  The 
  following 
  

   observations 
  were 
  made 
  in 
  connection 
  with 
  a 
  cooperative 
  study 
  of 
  

   insect 
  enemies 
  of 
  the 
  locust 
  by 
  the 
  Bureau 
  of 
  Entomology 
  and 
  the 
  

   Forest 
  Service 
  in 
  1905. 
  

  

  The 
  destructive 
  work 
  of 
  the 
  locust 
  leaf 
  -mining 
  beetle 
  (Odontota 
  dor- 
  

   sails 
  Thunb.) 
  & 
  and 
  the 
  locust 
  borer 
  (Cyllene 
  robinise 
  Forst.) 
  requires 
  

   special 
  consideration 
  wherever 
  the 
  establishment 
  of 
  forest 
  plantations 
  

   of 
  locust 
  is 
  desired 
  in 
  this 
  region. 
  

  

  The 
  locust 
  leaf-mining 
  beetle. 
  — 
  Severe 
  injury 
  by 
  the 
  leaf 
  -mining 
  bee- 
  

   tle 
  gives 
  the 
  trees 
  a 
  blighted, 
  brown 
  appearance 
  by 
  midsummer. 
  The 
  

   examination 
  of 
  a 
  locust 
  tree 
  early 
  in 
  July 
  reveals 
  blister 
  spots 
  on 
  the 
  

   leaves, 
  caused 
  by 
  the 
  young, 
  or 
  grub, 
  of 
  the 
  beetle, 
  a 
  small, 
  flattened, 
  

   whitish 
  worm, 
  which 
  eats 
  the 
  soft 
  tissue 
  between 
  the 
  upper 
  and 
  lower 
  

   surface. 
  Toward 
  the 
  end 
  of 
  July 
  the 
  beetles 
  begin 
  to 
  emerge 
  from 
  

   the 
  leaves 
  and 
  feed 
  upon 
  the 
  upper 
  surface. 
  The 
  combined 
  effect 
  of 
  

   the 
  blisters 
  and 
  the 
  subsequent 
  feeding 
  of 
  the 
  adult 
  insects 
  Tenders 
  

   the 
  foliage 
  partially 
  or 
  wholly 
  functionless, 
  according 
  to 
  the 
  severity 
  

   of 
  the 
  attack. 
  This 
  reduction 
  of 
  the 
  working 
  leaf 
  surface, 
  year 
  by 
  

   year, 
  weakens 
  the 
  tree, 
  since 
  it 
  is 
  not 
  able 
  to 
  produce 
  sufficient 
  food 
  

   to 
  maintain 
  its 
  growth. 
  Such 
  a 
  condition 
  alone, 
  or 
  in 
  conjunction 
  

   with 
  secondary 
  causes, 
  may 
  result 
  in 
  the 
  death 
  of 
  the 
  tree 
  within 
  a 
  

   few 
  years. 
  A 
  cross 
  section 
  of 
  the 
  stem 
  of 
  a 
  tree 
  attacked 
  for 
  several 
  

   years 
  shows 
  a 
  steady 
  decrease 
  in 
  the 
  width 
  of 
  the 
  rings 
  of 
  annual 
  

   growth. 
  During 
  the 
  stages 
  of 
  decline 
  and 
  death 
  the 
  locusts 
  have 
  no 
  

  

  a 
  Volume 
  III, 
  No. 
  5, 
  The 
  Monthly 
  Bulletin 
  of 
  the 
  Division 
  of 
  Zoology, 
  Pennsylvania 
  State 
  

   Department 
  of 
  Agriculture. 
  

  

  & 
  See 
  United 
  States 
  Department 
  of 
  Agriculture, 
  Division 
  of 
  Entomology, 
  Bulletin 
  No. 
  38, 
  

   new 
  series, 
  1902, 
  "The 
  Leaf 
  -mining 
  Locust 
  Beetle," 
  F. 
  H. 
  Chittenden. 
  

  

  