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  either 
  arsenate 
  of 
  lead 
  or 
  Paris 
  green 
  ; 
  but 
  where 
  it 
  is 
  more 
  extensive, 
  

   they 
  should 
  be 
  sprayed 
  with 
  one 
  ounce 
  of 
  arsenate 
  of 
  lead 
  in 
  each 
  

   gallon 
  of 
  water, 
  in 
  either 
  case 
  just 
  after 
  the 
  leaves 
  appear 
  above 
  

   ground. 
  A 
  little 
  of 
  the 
  dust 
  mixture 
  worked 
  into 
  the 
  soil 
  is 
  often 
  

   beneficial. 
  Another 
  successful 
  method 
  consists 
  of 
  putting 
  a 
  mixture 
  

   of 
  turpentine 
  and 
  lime 
  at 
  the 
  base 
  of 
  the 
  plants 
  and 
  covering 
  these 
  

   with 
  mosquito 
  netting. 
  If 
  the 
  ground 
  round 
  the 
  plants 
  is 
  hard, 
  

   the 
  larvae 
  will 
  be 
  killed 
  by 
  exposure 
  to 
  the 
  sun's 
  rays. 
  

  

  Brunner 
  (J.). 
  The 
  Sequoia 
  Pitch 
  Moth, 
  a 
  Menace 
  to 
  Pine 
  in 
  Western 
  

   Montana. 
  — 
  U.S. 
  Dept. 
  Agric, 
  Washington, 
  D.C., 
  Bull. 
  no. 
  Ill, 
  

   11th 
  July 
  1914, 
  11 
  pp., 
  5 
  figs. 
  

  

  Between 
  the 
  Swan 
  and 
  Clearwater 
  Eivers 
  in 
  Montana, 
  the 
  sequoia 
  

   pitch 
  moth 
  (Vespamima 
  sequoia, 
  Edw.) 
  is 
  a 
  very 
  serious 
  factor 
  in 
  

   forest 
  destruction 
  over 
  90,000 
  acres 
  of 
  forest. 
  V. 
  sequoia 
  has 
  prac- 
  

   tically 
  no 
  natural 
  enemies, 
  but 
  Dendroctonus 
  monticolae, 
  the 
  mountain 
  

   pine 
  beetle, 
  frequently 
  attacks 
  and 
  kills 
  trees 
  infested 
  by 
  the 
  larvae 
  of 
  

   F. 
  sequioa, 
  which 
  cannot 
  survive 
  without 
  the 
  flow 
  of 
  sap. 
  Outdoor 
  

   and 
  laboratory 
  observations 
  on 
  F. 
  sequoia 
  show 
  that 
  the 
  flight 
  of 
  the 
  

   mature 
  insects 
  and 
  oviposition 
  occur 
  between 
  25th 
  June 
  and 
  15th 
  July, 
  

   and 
  that 
  both 
  are 
  over 
  by 
  1st 
  August. 
  The 
  adult 
  is 
  rather 
  short-hved, 
  

   the 
  female 
  dying, 
  unless 
  fertilised, 
  within 
  three 
  days 
  after 
  emergence. 
  

   Few 
  eggs 
  are 
  deposited 
  in 
  any 
  one 
  place 
  and 
  it 
  was 
  observed 
  that 
  

   wherever 
  two 
  larvae 
  were 
  too 
  close 
  together, 
  one 
  invariably 
  died. 
  

   The 
  length 
  of 
  the 
  incubation 
  period 
  is 
  unknown, 
  but 
  injury 
  by 
  young 
  

   larvae 
  was 
  noticed 
  by 
  15th 
  August. 
  About 
  1st 
  October, 
  when 
  frost 
  

   arrests 
  their 
  activity, 
  the 
  larvae, 
  especially 
  the 
  females, 
  have 
  attained 
  

   considerable 
  size. 
  The 
  following 
  summer 
  is 
  spent 
  in 
  the 
  tunnel 
  in 
  

   the 
  pitch 
  exudation, 
  and 
  the 
  pupal 
  stage 
  occupies 
  30 
  days, 
  the 
  adults 
  

   emerging 
  two 
  years 
  after 
  the 
  egg 
  was 
  laid. 
  Large 
  flights 
  are 
  to 
  be 
  

   expected 
  during 
  1914, 
  1916, 
  1918, 
  etc., 
  unless 
  the 
  insect 
  is 
  controlled, 
  

   and 
  smaller 
  ones 
  during 
  1915, 
  1917, 
  1919, 
  etc. 
  The 
  insect 
  prefers 
  

   sunny 
  openings 
  within 
  the 
  forest, 
  slopes 
  where 
  the 
  soil 
  is 
  rather 
  sandy, 
  

   and 
  ridges 
  along 
  watercourses. 
  Although 
  it 
  attacks 
  all 
  kinds 
  of 
  

   conifers, 
  lodge 
  pole 
  pine 
  and 
  yellow 
  pine 
  seem 
  to 
  suffer 
  most. 
  Infested 
  

   trees 
  are 
  readily 
  located 
  by 
  the 
  pitch 
  exudation 
  over 
  the 
  tunnel 
  of 
  

   the 
  larva. 
  The 
  trees 
  are 
  attacked 
  at 
  the 
  extreme 
  base 
  and 
  the 
  

   exuding 
  pitch 
  often 
  flows 
  out 
  from 
  the 
  tree 
  10 
  or 
  12 
  inches 
  over 
  the 
  

   ground. 
  The 
  larva 
  begins 
  its 
  mine 
  in 
  a 
  crevice 
  of 
  the 
  bark, 
  where- 
  

   the 
  egg 
  was 
  deposited, 
  and 
  constructs 
  transverse 
  galleries 
  running 
  in 
  

   both 
  directions 
  from 
  the 
  point 
  of 
  entry 
  and 
  widens 
  this 
  tunnel 
  at 
  

   the 
  centre 
  to 
  produce 
  a 
  chamber. 
  In 
  small 
  trees 
  the 
  mine 
  is 
  

   always 
  nearly 
  straight 
  across 
  the 
  grain 
  of 
  the 
  wood. 
  Entire 
  girdhng 
  

   only 
  occurs 
  with 
  plural 
  infestation, 
  which 
  is 
  a 
  very 
  rare 
  occurrence, 
  

   as 
  the 
  larva 
  instinctively 
  avoids 
  destroying 
  its 
  own 
  food 
  supply 
  by 
  

   killing 
  the 
  tree. 
  

  

  Surface 
  fires 
  leave 
  moth-infested 
  trees 
  weak 
  and 
  w^ounded, 
  as 
  the 
  

   pitch 
  exudation 
  burns 
  readily. 
  The 
  only 
  way 
  to 
  reduce 
  the 
  numbers 
  

   of 
  F. 
  sequoia 
  appears 
  to 
  be 
  the 
  destruction 
  of 
  the 
  larvae 
  by 
  hand. 
  The 
  

   cost 
  of 
  this 
  might 
  be 
  reduced 
  by 
  the 
  collection 
  and 
  shipment 
  of 
  the 
  

   pitch, 
  since 
  analysis 
  of 
  these 
  resins, 
  received 
  from 
  the 
  U.S. 
  Bureau 
  

   of 
  Chemistry, 
  support 
  the 
  view 
  that 
  no 
  difiiculty 
  would 
  be 
  encountered 
  

   in 
  disposing 
  of 
  the 
  turpentine 
  produced 
  from 
  the 
  exudations. 
  

  

  