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  a 
  very 
  efficient 
  insecticide 
  against 
  plant 
  lice, 
  scale-insects, 
  etc. 
  Soluble 
  

   sulphur 
  compound 
  is 
  a 
  comparatively 
  new 
  spray 
  now 
  sold 
  throughout 
  

   the 
  United 
  States 
  and 
  Canada 
  and 
  claimed 
  to 
  be 
  equal 
  to 
  lime-sulphur. 
  

   It 
  has 
  been 
  tried 
  at 
  Corvallis 
  in 
  a 
  limited 
  way 
  against 
  the 
  San 
  Jose 
  

   scale 
  and 
  found 
  to 
  be 
  efficient. 
  Growers 
  should 
  not 
  assume 
  that 
  

   because 
  this 
  substance 
  and 
  lime-sulphur 
  are 
  similar 
  in 
  composition 
  

   the 
  one 
  can 
  in 
  all 
  cases 
  replace 
  the 
  other. 
  " 
  Atomic 
  sulphur," 
  primarily 
  

   used 
  for 
  fungous 
  diseases, 
  may 
  be 
  used 
  against 
  various 
  mites. 
  

   Pyrethrum 
  powder 
  may 
  be 
  used 
  either 
  as 
  a 
  powder 
  or 
  in 
  a 
  water 
  

   solution, 
  1 
  lb. 
  in 
  50 
  gals., 
  and 
  is 
  available 
  against 
  the 
  pear 
  and 
  cherry 
  

   slug 
  if 
  poisons 
  are 
  undesirable. 
  Kerosene 
  emulsion 
  is 
  always 
  

   satisfactory 
  if 
  the 
  emulsion 
  is 
  properly 
  prepared 
  from 
  good 
  materials. 
  

   A 
  standard 
  formula 
  is 
  : 
  — 
  Whale-oil 
  soap 
  J 
  lb., 
  water 
  1 
  gal., 
  kerosene 
  

   2 
  gals. 
  This 
  forms 
  3 
  gals, 
  of 
  stock 
  solution 
  which 
  can 
  be 
  diluted 
  

   to 
  any 
  required 
  strength 
  by 
  adding 
  water. 
  To 
  get 
  the 
  amount 
  

   of 
  water 
  for 
  any 
  given 
  percentage, 
  divide 
  200 
  by 
  the 
  percent^ 
  

   subtract 
  3 
  from 
  the 
  quotient, 
  and 
  this 
  gives 
  the 
  amount 
  of 
  water 
  

   necessary 
  to 
  add 
  to 
  each 
  3 
  gals, 
  of 
  stock 
  to 
  obtain 
  a 
  working 
  

   solution 
  of 
  the 
  required 
  strength. 
  Example 
  : 
  For 
  a 
  15 
  per 
  cent, 
  

   solution, 
  200 
  divided 
  by 
  15 
  gives 
  13 
  J 
  and 
  if 
  3 
  is 
  subtracted 
  the 
  result 
  

   is 
  lOJ. 
  If 
  lOJ 
  gals, 
  water 
  are 
  added 
  to 
  3 
  gals, 
  stock 
  a 
  15 
  per 
  cent, 
  

   working 
  solution 
  is 
  obtained. 
  Crude 
  oil 
  emulsion 
  is 
  somewhat 
  similar 
  

   to 
  kerosene 
  emulsion, 
  except 
  that 
  liquid 
  whale-oil 
  or 
  fish-oil 
  soap 
  should 
  

   always 
  be 
  used. 
  Distillate 
  oil 
  emulsion 
  is 
  not 
  yet 
  commonly 
  used 
  in 
  

   Oregon, 
  but 
  is 
  well 
  known 
  in 
  California, 
  where 
  it 
  is 
  combined 
  with 
  

   " 
  Black 
  Leaf-40 
  " 
  for 
  pear 
  thrips. 
  It 
  is 
  made 
  as 
  follows 
  : 
  — 
  Dissolve 
  30 
  lb. 
  

   of 
  whale-oil 
  soap 
  in 
  12 
  gals, 
  of 
  boiling 
  water, 
  and 
  add 
  20 
  gals, 
  of 
  dis- 
  

   tillate 
  (28 
  degrees 
  Beaume) 
  while 
  still 
  hot. 
  Mix 
  thoroughly 
  to 
  make 
  a 
  

   complete 
  emulsion. 
  One 
  part 
  of 
  this 
  stock 
  solution 
  is 
  diluted 
  with 
  

   20 
  parts 
  water 
  for 
  use. 
  

  

  All 
  the 
  foregoing 
  are 
  contact 
  poisons. 
  The 
  food 
  poisons 
  are 
  usually 
  

   arsenicals, 
  at 
  present 
  used 
  in 
  the 
  form 
  of 
  arsenate 
  of 
  lead 
  and 
  arsenite 
  

   of 
  zinc. 
  For 
  codling 
  moth 
  and 
  leaf-eating 
  insect 
  control, 
  arsenate 
  of 
  

   lead 
  is 
  now^ 
  the 
  standard 
  remedy. 
  Most 
  commercial 
  brands 
  are 
  a 
  

   mixture 
  of 
  the 
  two 
  arsenates 
  known 
  as 
  acid 
  and 
  neutral 
  arsenates 
  of 
  

   lead 
  ; 
  but 
  these 
  names 
  are 
  misleading 
  to 
  the 
  fruit-growler, 
  because 
  

   of 
  the 
  suggested 
  presence 
  of 
  an 
  acid 
  of 
  some 
  sort, 
  which 
  is 
  not 
  the 
  case. 
  

   The 
  Oregon 
  Experiment 
  Station 
  designates 
  them 
  as 
  lead 
  hydrogen 
  ^ 
  

   arsenate 
  and 
  basic 
  arsenate. 
  Experiments 
  have 
  shown 
  that 
  the 
  former 
  

   acts 
  more 
  quickly 
  and 
  being 
  more 
  finely 
  divided 
  will 
  remain 
  in 
  

   suspension 
  much 
  longer. 
  It 
  was 
  further 
  shown 
  that 
  in 
  combination 
  

   with 
  lime-sulphur 
  and 
  in 
  strengths 
  containing 
  equal 
  percentages 
  of 
  

   arsenic 
  oxide, 
  the 
  lead 
  hydrogen 
  arsenate 
  was 
  as 
  efficient 
  as, 
  or 
  more 
  

   efficient 
  than, 
  the 
  basic. 
  (This 
  does 
  not 
  mean 
  that 
  the 
  former 
  com- 
  

   bination 
  is 
  recommended 
  for 
  orchard 
  practice). 
  Considerable 
  

   experimental 
  work 
  yet 
  remains 
  to 
  be 
  done, 
  but 
  except 
  where 
  otherwise 
  

   directed, 
  the 
  lead 
  hydrogen 
  arsenate 
  is 
  recommended 
  w^hen 
  used 
  

   without 
  lime-sulphur. 
  

  

  A 
  combination 
  spray 
  has 
  both 
  insecticide 
  and 
  fungicide 
  properties. 
  

   As 
  a 
  winter 
  spray 
  one 
  application 
  of 
  lime-sulphur 
  each 
  year 
  will 
  do 
  

   more 
  for 
  the 
  neglected 
  orchard 
  than 
  can 
  be 
  done 
  in 
  any 
  other 
  way 
  by 
  

   the 
  same 
  expenditure 
  of 
  cash 
  and 
  energy. 
  It 
  not 
  only 
  destroys 
  the 
  

   San 
  Jose 
  scale, 
  but 
  it 
  may 
  also 
  destroy 
  the 
  branch 
  form 
  of 
  the 
  woolly 
  

  

  037 
  d2 
  

  

  