﻿98 
  

  

  In 
  an 
  experiment 
  made 
  June 
  IH, 
  189(), 
  with 
  chinch-bugs 
  killed 
  by 
  

   immersion 
  in 
  water 
  heated 
  nearly 
  but 
  not 
  quite 
  to 
  the 
  boiling 
  point, 
  

   dead 
  insects 
  were 
  placed 
  in 
  a 
  box 
  of 
  earth 
  in 
  the 
  open 
  air, 
  infected 
  

   with 
  spores 
  of 
  Sporotrichum 
  and 
  slightly 
  sprinkled 
  with 
  dirt. 
  To 
  pre- 
  

   vent 
  the 
  drying 
  out 
  of 
  the 
  box 
  it 
  was 
  moistened 
  daily, 
  and 
  the 
  sur- 
  

   face 
  of 
  the 
  earth 
  was 
  covered 
  with 
  a 
  layer 
  of 
  green 
  leaves. 
  Within 
  

   four 
  days 
  the 
  bodies 
  of 
  all 
  the 
  bugs 
  used 
  in 
  this 
  experiment 
  were 
  

   completely 
  covered 
  with 
  a 
  good 
  growth 
  of 
  Sporotrichum. 
  

  

  Burning 
  in 
  M^lnter 
  Quarters. 
  — 
  It 
  has 
  been 
  for 
  many 
  years 
  

   commoidy 
  recommended 
  by 
  entomologists 
  and 
  economic 
  writers, 
  that 
  

   rul)bish. 
  dead 
  grass, 
  and 
  the 
  like, 
  along 
  the 
  borders 
  of 
  fields, 
  be 
  

   l)urned 
  over 
  in 
  late 
  winter 
  or 
  early 
  spring, 
  as 
  a 
  means 
  of 
  destroying 
  

   in 
  their 
  winter 
  quarters 
  chinch-bugs 
  and 
  other 
  injurious 
  insects. 
  

   Doubt 
  having 
  been 
  recently 
  cast 
  upon 
  the 
  efficacy 
  of 
  this 
  method, 
  I 
  

   directed 
  in 
  March, 
  1895, 
  an 
  experiment 
  for 
  the 
  j)recise 
  determina- 
  

   tion 
  of 
  the 
  effect 
  of 
  such 
  burning 
  upon 
  hibernating 
  chinch-bugs 
  on 
  

   the 
  Experiment 
  Station 
  farm 
  at 
  Urbana. 
  This 
  experiment 
  was 
  re- 
  

   ported 
  March 
  27, 
  by 
  the 
  Assistant 
  in 
  cliarge 
  of 
  it. 
  Mr. 
  W. 
  (t. 
  John- 
  

   son, 
  and 
  his 
  report 
  is 
  given 
  herewith: 
  

  

  •'A 
  small 
  plot 
  of 
  orchard 
  grass 
  on 
  the 
  University 
  farm, 
  about 
  two 
  

   rods 
  wnde 
  by 
  four 
  rods 
  long, 
  was 
  carefully 
  and 
  thoroughly 
  searched 
  

   for 
  chinch-bugs 
  to-day. 
  The 
  bugs 
  were 
  found 
  very 
  numerous 
  in 
  and 
  

   about 
  the 
  base 
  of 
  every 
  stool 
  of 
  grass 
  examined. 
  Fourteen 
  bugs 
  were 
  

   counted 
  in 
  one 
  stool 
  and 
  nineteen 
  in 
  another: 
  l)ut 
  these 
  numbers 
  are 
  

   only 
  approximate 
  and 
  do 
  not 
  represent 
  the 
  whole 
  number 
  in 
  any 
  

   cluster 
  of 
  grass, 
  as 
  it 
  was 
  exceedingly 
  difficult 
  to 
  part 
  the 
  dense 
  

   bunches, 
  especially 
  in 
  and 
  about 
  the 
  roots, 
  just 
  at 
  the 
  surface 
  of 
  the 
  

   ground, 
  where 
  the 
  bugs 
  were 
  most 
  abundant. 
  

  

  The 
  plot 
  chosen 
  was 
  particularly 
  favorable 
  for 
  experimental 
  pur- 
  

   poses 
  from 
  the 
  fact 
  that 
  the 
  ground 
  was 
  thickl}' 
  matted 
  with 
  a 
  dense 
  

   growth 
  of 
  dead 
  grass, 
  which 
  was 
  extremely 
  dry 
  except 
  at 
  the 
  bases 
  

   of 
  the 
  stools, 
  where 
  it 
  was 
  still 
  green. 
  The 
  common 
  blue-grass 
  

   was 
  also 
  a1)undant 
  on 
  the 
  same 
  plot, 
  and 
  this, 
  together 
  with 
  the 
  

   orchard-grass, 
  made 
  a 
  bed 
  of 
  dry 
  brown 
  blades 
  and 
  stems 
  three 
  and 
  

   four 
  inches 
  deep 
  in 
  places. 
  The 
  chinch-])ugs 
  were 
  nestled 
  between 
  

   the 
  stems 
  of 
  the 
  stools 
  of 
  grass, 
  usually 
  just 
  at 
  the 
  surface 
  of 
  the 
  

   ground 
  ; 
  but 
  an 
  occasional 
  one 
  was 
  found 
  an 
  inch 
  or 
  so 
  below 
  the 
  

   surface, 
  between 
  the 
  stems. 
  Such 
  places 
  were 
  not 
  very 
  damp 
  and 
  

   were 
  packed 
  with 
  small 
  particles 
  of 
  dried 
  l)lades 
  and 
  other 
  rubl)ish; 
  

   while 
  the 
  main 
  stems 
  of 
  the 
  grass 
  were 
  green 
  about 
  two 
  inches 
  

   above 
  the 
  surface, 
  the 
  tops 
  having 
  dried 
  up 
  and 
  fallen 
  over, 
  deeply 
  

   iuibedding 
  the 
  green 
  portions. 
  

  

  At 
  one 
  end 
  of 
  the 
  plot 
  a 
  fire 
  was 
  started 
  which 
  burned 
  l)riskly 
  and 
  

   soon 
  covered 
  the 
  entire 
  area. 
  In 
  about 
  fifteen 
  minutes 
  I 
  carefully 
  

   examined 
  the 
  stools 
  of 
  grass 
  at 
  the 
  end' 
  where 
  the 
  fire 
  was 
  started, 
  

   and 
  other 
  places 
  later. 
  All 
  the 
  dead 
  brown 
  grass 
  was 
  burned 
  of!', 
  

   leaving 
  the 
  ground 
  bare, 
  excejit 
  where 
  the 
  clusters 
  of 
  orchard-grass 
  

  

  