﻿88 
  

  

  DECIDUOUS 
  FRUIT 
  INSECTS 
  AND 
  INSECTICIDES. 
  

  

  The 
  washing 
  made 
  practically 
  no 
  difference 
  in 
  the 
  killing 
  effect 
  of 
  

   the 
  lime-sulphur 
  spray, 
  the 
  time 
  of 
  killing 
  varying 
  from 
  13 
  to 
  15 
  days, 
  

   and 
  the 
  amount 
  of 
  foliage 
  consumed 
  varying 
  from 
  0.82 
  to 
  1.56 
  square 
  

   inches. 
  In 
  the 
  case 
  of 
  arsenate 
  of 
  lead, 
  however, 
  the 
  killing 
  effect 
  was 
  

   considerably 
  retarded. 
  The 
  length 
  of 
  time 
  required 
  to 
  kill 
  all 
  the 
  

   larvae 
  when 
  the 
  foliage 
  was 
  unwashed 
  was 
  7 
  days; 
  when 
  washed 
  15 
  

   minutes, 
  11 
  days; 
  when 
  washed 
  30 
  minutes, 
  17 
  days. 
  The 
  amount 
  

   of 
  feeding 
  was 
  0.38, 
  1.79, 
  and 
  5 
  square 
  inches, 
  respectively. 
  

  

  Experiment 
  VI. 
  

  

  To 
  compare 
  the 
  killing 
  effect 
  of 
  commercial 
  lime-sulphur 
  and 
  home- 
  

   boiled 
  lime-sulphur, 
  an 
  experiment 
  was 
  conducted 
  in 
  which 
  two 
  lots 
  

   of 
  each 
  kind 
  were 
  used 
  at 
  the 
  strength 
  of 
  1J-50. 
  The 
  commercial 
  

   products 
  tested 
  33° 
  Baume 
  and 
  the 
  home-boiled 
  30° 
  Baume. 
  The 
  

   results 
  are 
  shown 
  in 
  Table 
  VI. 
  

  

  Table 
  VI. 
  — 
  Tests 
  of 
  the 
  hilling 
  effect 
  on 
  the 
  fall 
  webworm 
  of 
  lime-sulphur, 
  commercial 
  

  

  and 
  home-boiled. 
  

  

  [Experiment 
  started 
  Aug. 
  27, 
  1912. 
  Benton 
  Harbor, 
  Mich., 
  20 
  larvae 
  in 
  each 
  lot.] 
  

  

  

  Larva? 
  dying 
  in 
  each 
  lot. 
  

  

  Date 
  of 
  examination. 
  

  

  Lot 
  1 
  

   (20 
  larvae- 
  

   Check 
  (un- 
  

   sprayed). 
  

  

  Lot 
  2 
  

  

  (20 
  larvae)— 
  

  

  Commercial 
  

  

  lime-sulphur, 
  

  

  1^-50. 
  

  

  Lot 
  3 
  

  

  (20 
  larvae- 
  

   Commercial 
  

   lime-sulphur, 
  

   11-50. 
  

  

  Lot 
  4 
  

   (20 
  larvae)— 
  

   Home-boiled 
  

   lime-sulphur, 
  

  

  li-50. 
  

  

  Lot 
  5 
  

   (20 
  larvae)— 
  

   Home-boiled 
  

   lime-sulphur, 
  

  

  li-50. 
  

  

  Aug. 
  30 
  

  

  

  

  

  1 
  

   3 
  

  

  7 
  

   6 
  

   3 
  

  

  

  Sept. 
  1 
  

  

  

  6 
  

  

  7 
  

   7 
  

  

  4 
  

   9 
  

   6 
  

   1 
  

  

  5 
  

  

  4 
  

  

  

  6 
  

  

  6 
  ; 
  

  

  

  9 
  

  

  9 
  

  

  

  

  19 
  

  

  1 
  

  

  5 
  

  

  

  

  Oct. 
  18 
  

  

  

  

  

  

  

  

  

  

  

  Total 
  number 
  dead 
  

  

  Number 
  of 
  days 
  required 
  to 
  kill 
  

   Square 
  inches 
  of 
  foliage 
  consumed 
  . 
  

  

  6 
  

   116.00 
  

  

  20 
  

  

  9 
  

  

  1.19 
  

  

  20 
  

   12 
  

  

  1.28 
  

  

  20 
  

  

  12 
  

  

  3.05 
  

  

  20 
  

  

  9 
  

  

  4.38 
  

  

  It 
  was 
  found 
  that 
  the 
  commercial 
  and 
  the 
  home-boiled 
  lime-sulphur 
  

   killed 
  all 
  the 
  larvae 
  in 
  the 
  same 
  average 
  length 
  of 
  time. 
  However, 
  the 
  

   rapidity 
  of 
  killing 
  was 
  slightly 
  greater, 
  and 
  the 
  amount 
  of 
  foliage 
  

   consumed 
  less, 
  where 
  the 
  commercial 
  material 
  was 
  used, 
  due 
  probably 
  

   to 
  the 
  fact 
  that 
  the 
  commercial 
  solution 
  was 
  somewhat 
  stronger, 
  which 
  

   the 
  Baume 
  tests 
  would 
  indicate. 
  

  

  Experiment 
  VII. 
  

  

  Lime-sulphur, 
  1J-50, 
  was 
  tried 
  out 
  on 
  a 
  limited 
  number 
  of 
  pear- 
  

   slug 
  larvae 
  (Eriocampoides 
  cerasi 
  L.), 
  since 
  only 
  a 
  few 
  were 
  available 
  

   for 
  this 
  test. 
  As 
  in 
  all 
  the 
  experiments, 
  the 
  insects 
  were 
  not 
  placed 
  

   upon 
  the 
  leaves 
  until 
  the 
  spray 
  had 
  thoroughly 
  dried. 
  The 
  results 
  

   are 
  shown 
  in 
  Table 
  VII. 
  

  

  