﻿210 
  W. 
  A. 
  LAMBORN. 
  — 
  THE 
  AGRICULTURAL 
  PESTS 
  

  

  The 
  pests 
  which 
  cause 
  most 
  damage 
  to 
  maize 
  in 
  the 
  fields 
  are 
  the 
  cob 
  and 
  stem 
  

   borers, 
  with 
  which 
  it 
  is 
  almost 
  impossible 
  to 
  deal 
  directly, 
  though, 
  as 
  pointed 
  out 
  by 
  

   my 
  predecessors, 
  their 
  numbers 
  could 
  certainly 
  be 
  reduced 
  by 
  a 
  cleaner 
  system 
  of 
  

   farming. 
  The 
  maize 
  on 
  the 
  native 
  farms 
  is 
  as 
  a 
  rule 
  allowed 
  to 
  remain 
  in 
  the 
  field 
  

   long 
  after 
  it 
  is 
  ripe, 
  so 
  that 
  it 
  becomes 
  infested 
  with 
  caterpillars 
  and 
  weevils 
  ; 
  it 
  

   should 
  unquestionably 
  be 
  harvested 
  as 
  early 
  as 
  possible 
  and 
  then 
  the 
  husks 
  and 
  stems 
  

   should 
  be 
  disposed 
  of. 
  The 
  native 
  practice 
  of 
  leaving 
  the 
  stems 
  still 
  standing 
  in 
  

   the 
  fields 
  and 
  of 
  training 
  up 
  the 
  yam 
  vine 
  on 
  them 
  cannot 
  be 
  too 
  strongly 
  discouraged, 
  

   for, 
  as 
  already 
  pointed 
  out, 
  the 
  borers 
  continue 
  to 
  feed 
  and 
  thrive 
  in 
  these 
  partly 
  dead 
  

   stems. 
  When 
  the 
  cobs 
  are 
  stripped, 
  also, 
  the 
  husks 
  are 
  littered 
  about, 
  many 
  con- 
  

   taining 
  larvae 
  and 
  pupae 
  of 
  pests. 
  

  

  The 
  ideal 
  method 
  of 
  disposing 
  of 
  maize 
  refuse 
  would 
  be 
  to 
  burn 
  it, 
  but 
  as 
  this 
  was 
  

   felt 
  to 
  be 
  undesirable 
  from 
  the 
  point 
  of 
  view 
  of 
  sound 
  farming, 
  a 
  series 
  of 
  experiments 
  

   were 
  made 
  with 
  a 
  view 
  to 
  testing 
  how 
  far 
  the 
  burial 
  of 
  refuse, 
  or 
  its 
  inclusion 
  in 
  com- 
  

   post 
  heaps 
  would 
  result 
  in 
  destruction 
  of 
  the 
  pests. 
  It 
  was 
  found 
  that 
  borers 
  in 
  maize 
  

   and 
  guinea-corn 
  refuse 
  perished 
  when 
  it 
  was 
  buried 
  under 
  a 
  few 
  inches 
  of 
  earth 
  in 
  the 
  

   wret 
  season, 
  when 
  doubtless 
  bacterial 
  action 
  and 
  other 
  fermentative 
  changes 
  set 
  up 
  

   in 
  the 
  fluids 
  in 
  the 
  stems 
  would 
  accelerate 
  their 
  death. 
  Formation 
  of 
  the 
  refuse 
  into 
  

   a 
  compost 
  heap 
  was 
  also 
  equally 
  effective. 
  

  

  The 
  problem 
  of 
  the 
  control 
  of 
  these 
  pests 
  therefore 
  resolves 
  itself 
  into 
  (a) 
  harvesting 
  

   as 
  early 
  as 
  possible, 
  and 
  (b) 
  clean 
  farming 
  ; 
  and 
  if 
  these 
  are 
  practised, 
  there 
  are 
  likely 
  

   to 
  be 
  fewer 
  pests 
  in 
  stored 
  grain. 
  

  

  Pests 
  Attacking 
  Stored 
  Maize. 
  

  

  On 
  my 
  arrival 
  in 
  late 
  May, 
  maize 
  in 
  the 
  store 
  was 
  found 
  to 
  be 
  severely 
  attacked 
  

   by 
  the 
  common 
  grain 
  weevil, 
  Calandra 
  oryzae, 
  L., 
  the 
  Tenebrionid 
  Tribolium 
  con- 
  

   fusum, 
  the 
  Trogositid 
  Tenebrioides 
  mauritanicus, 
  L., 
  and 
  by 
  a 
  fourth 
  smaller 
  brown 
  

   beetle, 
  in 
  addition 
  to 
  the 
  larvae 
  of 
  the 
  Pyralid 
  moths, 
  Mussidia 
  nigrivenella, 
  Rag., 
  

   and 
  Ephestia 
  cautella, 
  Walk., 
  and 
  all 
  these 
  pests 
  reappeared 
  in 
  great 
  force 
  in 
  the 
  

   new 
  maize 
  almost 
  as 
  soon 
  as 
  it 
  was 
  stored. 
  None 
  of 
  the 
  field 
  pests 
  other 
  than 
  these 
  

   was 
  found 
  to 
  attack 
  stored 
  maize. 
  

  

  As 
  showing 
  the 
  remarkable 
  instinct 
  possessed 
  by 
  these 
  pests 
  for 
  finding 
  food 
  for 
  

   themselves 
  and 
  their 
  offspring 
  it 
  may 
  be 
  mentioned 
  that, 
  in 
  early 
  November, 
  five 
  

   sacks 
  of 
  sound 
  maize, 
  apparently 
  free 
  from 
  insects, 
  were 
  placed 
  in 
  the 
  laboratory. 
  On 
  

   the 
  following 
  day 
  maize 
  beetles 
  and 
  moths 
  were 
  observed 
  to 
  be 
  flying 
  in 
  at 
  the 
  windows, 
  

   at 
  once 
  settling 
  on 
  the 
  sacks, 
  and 
  there 
  was 
  a 
  gradual 
  and 
  constant 
  invasion 
  subse- 
  

   quently, 
  so 
  that 
  at 
  the 
  end 
  of 
  December 
  the 
  grain 
  was 
  absolutely 
  riddled 
  by 
  them. 
  

   A 
  large 
  number 
  of 
  little 
  Chalcids 
  were 
  then 
  discovered 
  in 
  the 
  maize 
  and 
  it 
  was 
  subse- 
  

   quently 
  found 
  that 
  they 
  were 
  breeding 
  freely 
  in 
  larvae 
  of 
  Calandra, 
  though 
  owing 
  to 
  

   the 
  enormous 
  numbers 
  of 
  these 
  beetles 
  they 
  were 
  not 
  effective 
  as 
  a 
  check. 
  These 
  

   parasites 
  belong 
  to 
  a 
  new 
  species 
  of 
  Meraporus 
  (family 
  Pteromalidae) 
  which 
  will 
  

   shortly 
  be 
  described 
  by 
  Mr. 
  James 
  Waterston. 
  

  

  The 
  harvested 
  grain 
  was 
  placed 
  in 
  a 
  seed 
  store, 
  the 
  window 
  frames 
  of 
  which 
  were 
  

   filled 
  with 
  copper 
  mosquito 
  gauze 
  for 
  ventilation 
  purposes. 
  In 
  March, 
  a 
  dense 
  mass 
  

   of 
  the 
  moths 
  Ephestia 
  and 
  Mussidia 
  could 
  be 
  seen 
  early 
  each 
  morning 
  flying 
  up 
  and 
  

   down 
  on 
  the 
  outside 
  in 
  an 
  endeavour 
  to 
  find 
  an 
  entrance, 
  and 
  settling 
  down 
  quietly 
  

  

  