﻿188 
  REPORT 
  UNITED 
  STATES 
  ENTOMOLOGICAL 
  COMMISSION. 
  

  

  for 
  the 
  trees 
  at 
  25 
  cents 
  each, 
  as 
  orchards 
  average. 
  Of 
  course 
  the 
  ex- 
  

   pense 
  will 
  depend 
  largely 
  on 
  the 
  quality 
  of 
  the 
  lumber 
  used."^^ 
  

  

  Another 
  contrivance 
  is 
  an 
  old 
  one 
  that 
  has 
  been 
  employed 
  for 
  nearly 
  

   forty 
  years 
  in 
  Massachusetts, 
  and 
  lately 
  used 
  with 
  satisfaction 
  by 
  Mr. 
  

   John 
  G. 
  Barker 
  (when 
  gardener 
  to 
  Mr. 
  G. 
  G. 
  Hubbard), 
  of 
  Cambridge. 
  

  

  Fig. 
  7 
  is 
  a 
  section 
  of 
  the 
  whole 
  contrivance 
  — 
  a 
  a 
  being 
  the 
  zinc 
  roof 
  over 
  the 
  oil 
  

   troughs, 
  h 
  h; 
  d 
  d, 
  the 
  surface 
  of 
  the 
  earth 
  ; 
  c 
  c, 
  the 
  tar 
  or 
  lime 
  vphich 
  is 
  used 
  to 
  fill 
  the 
  

   box 
  around 
  the 
  tree. 
  

  

  Fig. 
  8 
  is 
  a 
  smaller 
  view 
  of 
  the 
  same. 
  The 
  box 
  is 
  square, 
  large 
  enough 
  to 
  leave 
  

   about 
  four 
  inches 
  of 
  space 
  around 
  the 
  tree 
  ; 
  is 
  sunk 
  some 
  four 
  inches 
  in 
  the 
  ground, 
  

   and 
  rises 
  about 
  ten 
  inches 
  above 
  the 
  surface. 
  The 
  trough 
  ,^i 
  i, 
  y, 
  

  

  is 
  in 
  shape 
  like 
  the 
  letter 
  V, 
  two 
  inches 
  deep, 
  and 
  is 
  made 
  x^^, 
  My- 
  

  

  FiG. 
  7. 
  — 
  Canker-worm 
  trap. 
  

  

  Fig. 
  8. 
  — 
  Canker-worm 
  trap 
  — 
  

   section. 
  

  

  by 
  a 
  tinman 
  before 
  nailing 
  on 
  the 
  box; 
  it 
  is 
  tacked 
  on 
  two 
  inches 
  below 
  the 
  upper 
  

   €dge 
  of 
  the 
  box, 
  and 
  then 
  the 
  roof 
  is 
  placed 
  in 
  position 
  and 
  secured 
  by 
  a 
  single 
  screw 
  

   into 
  the 
  upper 
  edge 
  of 
  each 
  side 
  or 
  board. 
  It 
  must, 
  of 
  course, 
  be 
  placed 
  in 
  a 
  level 
  

   position, 
  to 
  hold 
  the 
  oil. 
  This 
  is 
  done 
  by 
  means 
  of 
  a 
  spade 
  used 
  in 
  setting 
  the 
  box 
  in 
  

   the 
  earth. 
  The 
  box 
  and 
  roof 
  are 
  nearly 
  completed 
  in 
  the 
  tinshop, 
  but 
  the 
  corner 
  of 
  

   both 
  must 
  be 
  left 
  open 
  till 
  placed 
  around 
  the 
  tree, 
  when 
  the 
  parts 
  are 
  soldered 
  to- 
  

   gether. 
  The 
  roof 
  is 
  about 
  four 
  and 
  a 
  half 
  inches 
  wide, 
  with 
  the 
  outside 
  turned 
  under 
  

   about 
  the 
  fourth 
  of 
  an 
  inch, 
  to 
  keep 
  it 
  stiff 
  and 
  in 
  shape. 
  In 
  order 
  to 
  examine 
  the 
  oil, 
  

   and 
  to 
  see 
  that 
  all 
  is 
  right, 
  it 
  is 
  necessary 
  to 
  loosen 
  one 
  of 
  the 
  screws. 
  The 
  box 
  will 
  

   vary 
  somewhat 
  in 
  size 
  with 
  the 
  magnitude 
  of 
  the 
  tree; 
  with 
  a 
  trunk 
  six 
  inches 
  in 
  

   diameter, 
  the 
  box 
  should 
  be 
  about 
  fourteen 
  inches 
  square 
  and 
  fourteen 
  inches 
  high; 
  

   for 
  a 
  trunk 
  a 
  foot 
  in 
  diameter, 
  it 
  should 
  be 
  about 
  twenty 
  inches 
  square; 
  but 
  a 
  vari- 
  

   ation 
  of 
  two 
  or 
  three 
  inches 
  would 
  not 
  be 
  of 
  great 
  importance. 
  A 
  few 
  inches 
  of 
  tan- 
  

   bark 
  or 
  lime 
  placed 
  within, 
  is 
  for 
  the 
  purpose 
  of 
  preventing 
  the 
  moths 
  from 
  ascending 
  

   inside. 
  One 
  pint 
  of 
  crude 
  petroleum 
  (costing 
  3 
  cents 
  per 
  tree, 
  at 
  24 
  cents 
  per 
  gallon) 
  

   is 
  enough 
  for 
  each 
  tree. 
  

  

  With 
  a 
  little 
  care 
  in 
  making 
  a 
  close 
  connection 
  between 
  the 
  Y-shaped 
  

   trough 
  and 
  the 
  box, 
  the 
  above 
  contrivance 
  must 
  work 
  to 
  perfection, 
  as 
  

   indeed 
  Mr. 
  Barker 
  found 
  it 
  to 
  do. 
  Yet 
  on 
  account 
  of 
  the 
  greater 
  labor 
  

   and 
  exx)ense 
  of 
  making 
  and 
  using 
  it, 
  and 
  of 
  the 
  greater 
  dilhculty 
  of 
  ex- 
  

   amining 
  beneath 
  it, 
  the 
  hanging 
  tin 
  band, 
  described 
  as 
  used 
  by 
  Mr. 
  

   Jones, 
  is 
  preferable. 
  

  

  Belts 
  of 
  cotton 
  wool 
  have 
  been 
  used 
  to 
  entangle 
  the 
  feet 
  of 
  the 
  moths, 
  

   and 
  collars' 
  of 
  tin 
  plate, 
  fastened 
  around 
  the 
  trees 
  and 
  sloping 
  down- 
  

   wards 
  like 
  an 
  inverted 
  funnel, 
  have 
  been 
  proposed, 
  upon 
  the 
  supposi- 
  

   tion 
  that 
  the 
  moths 
  would 
  not 
  be 
  able 
  to 
  creep 
  in 
  an 
  inverted 
  position 
  

   beneath 
  the 
  smooth 
  and 
  sloping 
  surface. 
  

  

  100 
  From 
  a 
  newspaper 
  cutting. 
  

  

  