﻿REPORT 
  OF 
  THE 
  STATE 
  ENTOMOLOGIST 
  I9OO 
  98/ 
  

  

  blowing 
  in 
  a 
  direction 
  opposite 
  to 
  that 
  in 
  which 
  it 
  blew 
  while 
  the 
  first 
  

   spraying 
  was 
  in 
  progress. 
  An 
  examination 
  of 
  their 
  orchards 
  Sep. 
  ii 
  

   showed 
  that 
  living 
  scales 
  were 
  relatively 
  very 
  few, 
  and 
  that 
  the 
  trees 
  were 
  

   in 
  excellent 
  condition. 
  The 
  persistence 
  of 
  the 
  oil 
  on 
  the 
  trees 
  for 
  some 
  

   weeks 
  is 
  unfavorable 
  to 
  the 
  establishment 
  of 
  young 
  scales, 
  and 
  this 
  is 
  

   undoubtedly 
  a 
  valuable 
  aid 
  in 
  keeping 
  the 
  pests 
  under 
  control. 
  

  

  It 
  will 
  be 
  seen 
  that 
  even 
  after 
  spraying 
  a 
  tree 
  with 
  undiluted 
  

   petroleum, 
  a 
  few 
  scales 
  may 
  escape, 
  doubtless 
  because 
  the 
  oil 
  failed 
  to 
  

   reach 
  them 
  for 
  some 
  cause 
  or 
  other. 
  The 
  effects 
  on 
  the 
  trees 
  indicate 
  

   most 
  clearly 
  the 
  necessity 
  of 
  the 
  greatest 
  caution 
  in 
  spraying 
  with 
  such 
  

   oil. 
  In 
  fact, 
  it 
  can 
  not 
  be 
  advised. 
  These 
  trees 
  were 
  sprayed 
  at 
  a 
  time 
  

   when 
  they 
  should 
  be 
  most 
  resistant, 
  and 
  several 
  of 
  them 
  were 
  in 
  full 
  

   vigor 
  and 
  had 
  been 
  scarcely 
  affected 
  by 
  the 
  pest, 
  and 
  they 
  should 
  there- 
  

   fore, 
  theoretically, 
  be 
  in 
  better 
  condition 
  to 
  withstand 
  the 
  effects 
  of 
  the 
  

   insecticide. 
  One 
  tree 
  came 
  through 
  the 
  ordeal 
  safely, 
  another 
  lost 
  a 
  

   number 
  of 
  its 
  limbs 
  and 
  the 
  other 
  two 
  died. 
  

  

  It 
  is 
  true 
  that 
  subsequent 
  experience 
  has 
  led 
  Dr 
  Smith 
  to 
  regard 
  a 
  

   crude 
  petroleum 
  not 
  testing 
  43° 
  or 
  over 
  on 
  the 
  Beaume 
  oil 
  scale 
  as 
  dan- 
  

   gerous 
  to 
  use 
  undiluted. 
  Dr 
  Smith 
  states 
  that 
  a 
  safe 
  oil 
  for 
  use 
  in 
  this 
  

   manner 
  must 
  not 
  only 
  meet 
  the 
  specific 
  gravity 
  test 
  but 
  it 
  mast 
  be 
  either 
  

   a 
  green 
  or 
  an 
  amber 
  paraffin 
  oil, 
  not 
  an 
  asphaltum 
  oil. 
  The 
  above 
  ex- 
  

   periments 
  show 
  that 
  a 
  heavier 
  oil 
  can 
  be 
  used 
  in 
  a 
  mechanical 
  emulsion 
  

   without 
  apparent 
  injury 
  to 
  dormant 
  trees 
  and 
  the 
  successful 
  control 
  of 
  

   the 
  scale 
  by 
  Mr 
  Hart 
  indicates 
  that 
  even 
  if 
  the 
  oil 
  be 
  a 
  light 
  one 
  and 
  

   therefore 
  harmless 
  in 
  its 
  native 
  condition, 
  it 
  is 
  also 
  very 
  effective 
  when 
  

   diluted. 
  The 
  dilution 
  saves 
  oil, 
  aids 
  in 
  giving 
  a 
  more 
  uniform 
  distribution 
  

   of 
  the 
  insecticide 
  and 
  as 
  a 
  coarser 
  spray 
  can 
  be 
  used, 
  the 
  work 
  may 
  be 
  

   done 
  more 
  rapidly. 
  The 
  outfit 
  necessary 
  for 
  making 
  a 
  mechanical 
  mix- 
  

   ture 
  is 
  more 
  expensive 
  than 
  an 
  ordinary 
  spraying 
  apparatus 
  but 
  the 
  sav- 
  

   ing 
  in 
  oil 
  would 
  soon 
  make 
  the 
  difference, 
  if 
  the 
  operations 
  were 
  of 
  any 
  

   magnitude. 
  An 
  improvement 
  has 
  been 
  made 
  in 
  mechanical 
  sprayers 
  in 
  

   that 
  the 
  oil 
  and 
  water 
  are 
  conducted 
  in 
  separate 
  tubes 
  to 
  the 
  nozzle, 
  thus 
  

   preventing 
  the 
  separation 
  of 
  the 
  oil 
  and 
  water 
  in 
  the 
  hose. 
  This 
  device 
  

   is 
  made 
  by 
  a 
  Canadian 
  firm. 
  A 
  mechanical 
  dilution 
  of 
  crude 
  petroleum 
  

   is 
  much 
  safer, 
  apparently 
  just 
  as 
  effective 
  and 
  its 
  use 
  is 
  therefore 
  advised. 
  

  

  Whale 
  oil 
  soap. 
  The 
  trees 
  were 
  not 
  injured 
  by 
  the 
  application 
  of 
  this 
  

   insecticide, 
  even 
  at 
  the 
  rate 
  of 
  2 
  pounds 
  to 
  the 
  gallon. 
  They 
  were 
  very 
  

   thoroughly 
  sprayed, 
  and 
  the 
  scale 
  was 
  undoubtedly 
  severely 
  checked, 
  but 
  

   the 
  results 
  were 
  not 
  equal 
  to 
  those 
  obtained 
  with 
  a 
  20 
  % 
  crude 
  petroleum 
  

   emulsion. 
  The 
  two 
  treatments 
  with 
  whale 
  oil 
  soap 
  solutions 
  left 
  the 
  trees 
  

  

  