﻿15 
  

  

  (1) 
  Leaf-roller 
  eggs 
  possess 
  a 
  remarkable 
  resistance 
  to 
  injury 
  by 
  

   practically 
  all 
  well-known 
  contact 
  sprays 
  ; 
  (2) 
  lime 
  and 
  sulphur 
  

   preparations, 
  either 
  home-prepared 
  or 
  of 
  commercial 
  manufacture, 
  

   give 
  little, 
  if 
  any, 
  benefit, 
  even 
  when 
  used 
  in 
  excessive 
  strengths 
  ; 
  

   (3) 
  kerosene 
  emulsion 
  containing 
  16| 
  per 
  cent, 
  oil, 
  or 
  more, 
  usually 
  

   kills 
  the 
  eggs, 
  but 
  under 
  certain 
  conditions, 
  which 
  cannot 
  be 
  

   explained, 
  higher 
  strengths 
  may 
  fail 
  to 
  do 
  so 
  ; 
  on 
  the 
  other 
  hand, 
  a 
  

   weaker 
  strength 
  will 
  often 
  do 
  the 
  work 
  well 
  ; 
  (4) 
  a 
  thick 
  coating 
  with 
  

   a 
  Hme 
  whitewash 
  will 
  keep 
  the 
  larvae 
  from 
  emerging 
  from 
  the 
  eggs 
  ; 
  

   it 
  must 
  be 
  sufficient 
  to 
  cover 
  the 
  surface 
  of 
  the 
  egg-mass 
  entirely 
  ; 
  

   (5) 
  " 
  Black 
  Leaf 
  40," 
  " 
  Nicofume," 
  and 
  other 
  tobacco 
  preparations, 
  

   used 
  alone 
  or 
  with 
  soap, 
  were 
  of 
  no 
  value 
  ; 
  (6) 
  strong 
  arsenical 
  sprays 
  

   used 
  to 
  coat 
  the 
  egg-masses 
  may 
  be 
  of 
  some 
  benefit, 
  but 
  probably 
  

   not 
  enough 
  to 
  justify 
  their 
  use 
  ; 
  (7) 
  whale-oil 
  soap, 
  lye, 
  corrosive 
  

   subhmate. 
  Cooper's 
  " 
  V. 
  Tree 
  Spray," 
  " 
  Aphine," 
  and 
  hydrocyanic 
  

   acid 
  gas 
  gave 
  little 
  or 
  no 
  protection. 
  

  

  Abundant 
  notes 
  of 
  orchard 
  experiments 
  follow. 
  From 
  them 
  the 
  

   authors 
  conclude 
  that 
  : 
  — 
  

  

  (1) 
  The 
  leaf-roller 
  eggs 
  may 
  be 
  killed 
  by 
  a 
  very 
  thorough 
  spraying 
  

   with 
  a 
  soluble 
  oil 
  while 
  the 
  trees 
  are 
  dormant 
  ; 
  this 
  spray 
  should 
  

   probably 
  be 
  applied 
  prior 
  to, 
  but 
  as 
  near 
  hatching 
  time 
  of 
  the 
  eggs 
  

   as 
  possible 
  ; 
  (2) 
  very 
  careful 
  and 
  heavy 
  spraying 
  with 
  arsenicals 
  

   early 
  in 
  the 
  season 
  w^U 
  result 
  in 
  almost 
  complete 
  control 
  ; 
  the 
  first 
  

   application 
  should 
  be 
  made 
  shortly 
  after 
  the 
  eggs 
  begin 
  to 
  hatch, 
  

   which 
  will 
  be 
  when 
  the 
  first 
  green 
  foliage 
  is 
  showing 
  on 
  the 
  trees, 
  

   and 
  the 
  second 
  as 
  soon 
  as 
  the 
  blossom 
  buds 
  have 
  separated 
  in 
  the 
  

   clusters 
  ; 
  a 
  blossom 
  spray 
  is, 
  in 
  all 
  probability, 
  not 
  necessary, 
  and 
  is 
  

   dangerous, 
  in 
  that 
  it 
  poisons 
  the 
  bees 
  ; 
  (3) 
  " 
  Black 
  Leaf 
  40 
  " 
  care- 
  

   fully 
  and 
  thoroughly 
  applied 
  about 
  the 
  same 
  dates 
  as 
  the 
  first 
  two 
  

   sprayings 
  with 
  arsenicals, 
  will 
  give 
  good 
  results 
  ; 
  (4) 
  a 
  mixed 
  spray 
  

   of 
  " 
  Black 
  Leaf 
  40 
  " 
  and 
  lead 
  arsenate 
  is 
  little 
  more 
  satisfactory 
  than 
  

   either 
  one 
  of 
  the 
  insecticides 
  used 
  alone 
  ; 
  furthermore, 
  the 
  cost 
  of 
  

   such 
  spray 
  would 
  be 
  too 
  great 
  for 
  practical 
  purposes 
  ; 
  (5) 
  3 
  lb. 
  lead 
  

   arsenate 
  to 
  50 
  gals, 
  of 
  water 
  is 
  sufficient 
  for 
  successful 
  control, 
  and 
  

   there 
  is 
  no 
  advantage 
  to 
  be 
  derived 
  from 
  mixing 
  Paris 
  green 
  with 
  it, 
  

   as 
  many 
  have 
  done 
  ; 
  (6) 
  not 
  less 
  than 
  ten 
  gallons 
  of 
  spray, 
  on 
  an 
  

   average, 
  should 
  be 
  applied 
  to 
  trees 
  from 
  twelve 
  to 
  twenty 
  years 
  of 
  

   age 
  ; 
  very 
  large 
  trees 
  may 
  require 
  even 
  more 
  ; 
  (7) 
  failure 
  to 
  control 
  

   this 
  pest 
  with 
  arsenicals 
  has 
  been 
  due 
  in 
  most 
  cases 
  either 
  to 
  a 
  failure 
  

   to 
  spray 
  early 
  enough 
  and 
  at 
  the 
  correct 
  time, 
  or 
  to 
  put 
  enough 
  of 
  

   the 
  Hquid 
  on 
  the 
  trees. 
  

  

  Moore 
  (H. 
  W. 
  B.). 
  The 
  Planters' 
  Insect 
  Fnends.—Timehri, 
  

  

  Jl. 
  R. 
  Agric. 
  Comm, 
  Soc. 
  Brit. 
  Guiana, 
  iii, 
  no. 
  1, 
  Sept. 
  1913, 
  

   pp. 
  35-42. 
  

  

  An 
  account 
  of 
  the 
  insect 
  pests 
  which 
  attack 
  sugar-cane 
  in 
  British 
  

   Guiana 
  and 
  the 
  various 
  parasites 
  which 
  prey 
  upon 
  them. 
  A 
  paper 
  

   on 
  the 
  same 
  subject 
  by 
  Mr. 
  G. 
  E. 
  Bodkin 
  has 
  recently 
  been 
  noticed 
  

   in 
  this 
  Revieiv 
  (vol. 
  i, 
  "ser. 
  A, 
  p. 
  139). 
  

  

  