﻿629 
  

  

  FuLLAWAY 
  (D. 
  T.). 
  Tobacco 
  Insects 
  in 
  Hawaii. 
  — 
  Hawaii 
  Agric. 
  Expt. 
  

   Sta., 
  Honolulu, 
  Bull. 
  no. 
  34, 
  25th 
  May 
  1914, 
  20 
  pp., 
  9 
  figs. 
  

   [Keceived 
  28tli 
  October 
  1914.] 
  

  

  Elydna{Caradrina)reclusa 
  is 
  the 
  cutworm 
  most 
  commonly 
  found 
  in 
  the 
  

   tobacco 
  fields 
  in 
  Hawaii 
  and 
  is 
  a 
  recently 
  introduced 
  species, 
  probably 
  

   from 
  Fiji. 
  The 
  duration 
  of 
  the 
  larval 
  stage 
  is 
  from 
  30 
  to 
  40 
  days, 
  

   pupation 
  taking 
  place 
  an 
  inch 
  or 
  two 
  below 
  the 
  surface 
  of 
  the 
  soil, 
  

   the 
  moth 
  emerging 
  12 
  or 
  14 
  days 
  later. 
  Owing 
  to 
  the 
  ravages 
  

   of 
  this 
  species 
  six 
  or 
  seven 
  replantings 
  are 
  often 
  required 
  to 
  secure 
  a 
  

   crop, 
  in 
  spite 
  of 
  the 
  thorough 
  distribution 
  of 
  poisoned 
  bait 
  and 
  of 
  

   hand 
  picking. 
  Inabihty 
  to 
  control 
  the 
  cutworms 
  in 
  these 
  plantations 
  

   is 
  due 
  largely 
  to 
  the 
  rocky 
  and 
  unworkable 
  land. 
  With 
  thorough 
  

   cultivation, 
  cutworms 
  become 
  almost 
  a 
  neghgible 
  quantity 
  after 
  

   the 
  lapse 
  of 
  several 
  years, 
  except 
  for 
  occasional 
  outbreaks 
  which, 
  

   in 
  the 
  case 
  of 
  most 
  species, 
  are 
  of 
  rare 
  occurrence. 
  Next 
  to 
  thorough 
  

   cultivation 
  the 
  best 
  artificial 
  control 
  of 
  cutworms 
  consist? 
  of 
  distri- 
  

   buting 
  about 
  the 
  plants 
  a 
  poisoned 
  bait 
  consisting 
  of 
  white 
  arsenic 
  

   or 
  Paris 
  green 
  in 
  moistened 
  and 
  sweetened 
  bran, 
  flour, 
  or 
  middhngs. 
  

   The 
  edges 
  of 
  fields 
  adjacent 
  to 
  uncultivated 
  land 
  are 
  often 
  trenched, 
  

   so 
  as 
  to 
  present 
  a 
  steep 
  surface 
  on 
  the 
  exposed 
  side 
  which 
  the 
  cut- 
  

   worm 
  cannot 
  chmb. 
  Handpicking, 
  sometimes 
  resorted 
  to, 
  is 
  slow 
  

   and 
  expensive. 
  Parasites 
  are 
  fairly 
  efficient 
  throughout 
  the 
  year, 
  

   and 
  include 
  the 
  Tachinids, 
  Frontina 
  archippivora 
  and 
  Chaetogaedia 
  

   monticola, 
  the 
  ichneumon, 
  Polyophineta 
  (Ichneumon) 
  koebelei, 
  and 
  

   the 
  egg-parasite, 
  Trichogramma 
  pretiosum. 
  The 
  last-named, 
  or 
  T.flavum, 
  

   which 
  is 
  perhaps 
  identical 
  with 
  T. 
  pretiosum, 
  has 
  been 
  bred 
  from 
  the 
  

   eggs 
  of 
  a 
  Noctuid, 
  probably 
  Laphygma 
  [Spodoptera) 
  exigua. 
  Birds 
  

   also 
  devour 
  large 
  numbers 
  of 
  cutworms 
  and 
  should 
  be 
  protected. 
  

  

  Phthorimaea 
  operculella, 
  the 
  tobacco 
  sphtworm, 
  was 
  first 
  noticed 
  

   in 
  Hawaii 
  in 
  1892. 
  This 
  species 
  is 
  most 
  injurious 
  to 
  seedling 
  plants, 
  

   but 
  this 
  may 
  be 
  partly 
  overcome 
  by 
  seeding 
  the 
  beds 
  very 
  thinly 
  

   and 
  protecting 
  them 
  from 
  the 
  moth 
  with 
  cotton 
  netting. 
  The 
  damage 
  

   is 
  usually 
  sHght 
  on 
  well-conducted 
  plantations. 
  The 
  larvae 
  are 
  

   protected 
  in 
  their 
  tunnels, 
  but 
  when 
  deserting 
  an 
  old 
  mine 
  for 
  a 
  new 
  

   one 
  are 
  vulnerable 
  to 
  lead 
  arsenate 
  dusted 
  or 
  sprayed 
  on 
  the 
  plants, 
  

   and 
  this 
  measure 
  is 
  recommended 
  for 
  their 
  control 
  in 
  seed-beds. 
  No 
  

   solanaceous 
  plants 
  should 
  be 
  grown 
  near 
  the 
  tobacco 
  fields 
  and 
  all 
  

   solanaceous 
  weeds 
  in 
  the 
  immediate 
  vicinity 
  should 
  be 
  periodically 
  

   destroyed. 
  The 
  larvae 
  are 
  very 
  much 
  parasitised 
  by 
  a 
  Braconid, 
  

   Chelonus 
  blacJcburni, 
  which 
  also 
  attacks 
  a 
  number 
  of 
  other 
  small 
  

   leaf 
  -rolling 
  caterpillars. 
  The 
  parasitised 
  caterpillars 
  spin 
  their 
  

   cocoons 
  when 
  about 
  half-grown, 
  without 
  pupating, 
  and 
  shortly 
  after- 
  

   wards 
  the 
  larva 
  of 
  the 
  parasite 
  emerges 
  from 
  the 
  caterpillar, 
  and 
  

   feeding 
  on 
  it 
  externally, 
  kills 
  it 
  and 
  spins 
  its 
  own 
  cocoon 
  inside 
  that 
  

   of 
  its 
  host. 
  The 
  parasite 
  emerges 
  a 
  little 
  later 
  than 
  the 
  moth 
  would 
  

   have 
  done. 
  A 
  native 
  ichneumon, 
  Limnerium 
  blackburni, 
  is 
  also 
  parasitic 
  

   on 
  P. 
  operculella. 
  

  

  The 
  larva 
  of 
  Chloridea 
  (Heliothis) 
  ohsoleta 
  bores 
  into 
  and 
  eats 
  

   the 
  seed 
  pods 
  of 
  tobacco 
  and 
  also 
  eats 
  the 
  foliage 
  to 
  some 
  

   extent. 
  In 
  Hawaii 
  it 
  is 
  never 
  found 
  on 
  either 
  maize 
  or 
  cotton 
  

   and 
  is 
  not 
  generally 
  considered 
  a 
  serious 
  pest 
  of 
  tobacco, 
  as 
  its 
  mul- 
  

   tiplication 
  is 
  probably 
  checked 
  by 
  natural 
  enemies. 
  It 
  is 
  the 
  general 
  

  

  