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  recommended 
  ; 
  repellent 
  washes 
  that 
  depend 
  upon 
  their 
  odour 
  for 
  

   their 
  effect 
  are 
  useless 
  ; 
  coatings 
  intended 
  to 
  present 
  physical 
  difficulties 
  

   to 
  the 
  entrance 
  of 
  the 
  larvae 
  are 
  ineffective 
  ; 
  poison 
  coatings 
  are 
  too 
  

   readily 
  washed 
  off 
  ; 
  and 
  materials 
  used 
  at 
  the 
  base 
  as 
  repellents 
  are 
  

   ineffective 
  and 
  in 
  some 
  cases 
  dangerous. 
  Banking 
  earth 
  against 
  the 
  

   trunks 
  to 
  the 
  height 
  of 
  six 
  inches 
  or 
  more 
  has 
  proved 
  the 
  best 
  practice 
  

   that 
  can 
  be 
  recommended, 
  as 
  the 
  larvae 
  are 
  thus 
  driven 
  to 
  enter 
  at 
  a 
  

   higher 
  point 
  than 
  normally 
  would 
  be 
  the 
  case. 
  This 
  facilitates 
  the 
  

   removal 
  of 
  the 
  larva 
  and 
  reduces 
  the 
  cost. 
  Extracting 
  the 
  larvae 
  

   is 
  certainly 
  effective 
  and 
  when 
  done 
  carefully 
  need 
  not 
  injure 
  the 
  trees. 
  

   This 
  should 
  be 
  done 
  with 
  a 
  sharp 
  knife 
  and 
  a 
  light 
  wire 
  ending 
  in 
  a 
  

   small 
  hook 
  ; 
  with 
  this 
  the 
  larvae 
  can 
  often 
  be 
  drawn 
  from 
  the 
  burrow. 
  

   The 
  trees 
  should 
  be 
  " 
  wormed 
  " 
  as 
  late 
  in 
  the 
  autumn 
  as 
  practicable 
  

   and 
  again 
  in 
  May. 
  To 
  facilitate 
  the 
  w^ork 
  the 
  earth 
  should 
  be 
  drawn 
  

   away 
  from 
  the 
  trunks 
  to 
  a 
  depth 
  of 
  six 
  inches 
  and 
  the 
  root 
  crowns 
  

   scraped 
  at 
  least 
  one 
  day 
  before 
  the 
  " 
  worming 
  " 
  is 
  begun. 
  The 
  paper 
  

   concludes 
  with 
  a 
  lengthy 
  bibliography. 
  

  

  Davis 
  (J. 
  J.). 
  Common 
  white-grubs. 
  — 
  U.S. 
  Dept. 
  Agric, 
  Washington^ 
  

   Farmers' 
  Bull. 
  543, 
  18th 
  Julv 
  1913, 
  20 
  pp. 
  12 
  figs. 
  [Received 
  

   5th 
  Feb. 
  1914.] 
  

  

  The 
  most 
  serious 
  outbreak 
  of 
  white 
  grubs 
  (Lachnosterna) 
  recorded 
  

   in 
  the 
  States 
  occurred 
  in 
  1912, 
  when 
  over 
  12 
  milHon 
  dollars 
  worth 
  of 
  

   damage 
  was 
  done, 
  mostly 
  in 
  Iowa, 
  Wisconsin, 
  Illinois, 
  Pennsylvania, 
  

   New 
  York, 
  Connecticut 
  and 
  New 
  Jersey. 
  Available 
  records 
  show 
  

   that 
  May 
  beetles 
  were 
  unusually 
  abundant 
  in 
  1908, 
  the 
  grubs 
  causing 
  

   considerable 
  damage 
  in 
  Wisconsin, 
  Illinois, 
  etc. 
  in 
  1909, 
  and 
  yet 
  more 
  

   in 
  1912. 
  The 
  beetles 
  were 
  very 
  numerous 
  in 
  the 
  spring 
  of 
  1911, 
  thus 
  

   giving 
  rather 
  conclusive 
  evidence 
  that 
  the 
  hfe-cycle 
  of 
  the 
  more 
  

   abundant 
  and 
  numerous 
  species 
  in 
  those 
  localities 
  is 
  uniformly 
  three 
  

   years. 
  It 
  is, 
  therefore, 
  reasonably 
  certain 
  that 
  in 
  1914 
  the 
  beetles 
  

   will 
  again 
  be 
  unusually 
  plentiful, 
  and 
  the 
  year 
  following 
  (1915) 
  the 
  

   grubs 
  will 
  be 
  exceedingly 
  abundant 
  and 
  destructive 
  if 
  uncontrolled, 
  

   either 
  naturally 
  or 
  artificially. 
  The 
  grubs 
  do 
  the 
  greatest 
  amount 
  of 
  

   damage 
  in 
  their 
  second 
  year 
  and 
  to 
  the 
  early 
  plantings 
  in 
  their 
  third 
  

   year. 
  From 
  all 
  observations 
  small 
  grains 
  are 
  less 
  attacked 
  than 
  are 
  

   corn, 
  timothy, 
  strawberries 
  and 
  potatoes. 
  It 
  is 
  important 
  that 
  the 
  

   grubs 
  of 
  May 
  beetles 
  should 
  not 
  be 
  confused 
  with 
  similar 
  but 
  non- 
  

   injurious 
  grubs, 
  or 
  with 
  others 
  which 
  may 
  be 
  injurious 
  but 
  require 
  

   different 
  methods 
  of 
  control. 
  The 
  grubs 
  of 
  May 
  beetles 
  are 
  not 
  known 
  

   to 
  breed 
  in 
  manure 
  or 
  refuse 
  of 
  any 
  kind 
  ; 
  those 
  generally 
  found 
  in 
  such 
  

   places 
  being 
  the 
  immature 
  forms 
  of 
  certain 
  brown 
  beetles 
  (Ligyrus 
  

   gibbosus, 
  de 
  G., 
  and 
  L. 
  relictus, 
  Say) 
  w^hich 
  frequent 
  fight 
  in 
  the 
  same 
  

   manner 
  as 
  the 
  May 
  beetle. 
  The 
  white 
  grubs 
  and 
  May 
  beetles 
  are 
  

   preyed 
  upon 
  by 
  numerous 
  enemies, 
  the 
  most 
  important 
  being 
  birds, 
  

   in 
  the 
  stomachs 
  of 
  60 
  species 
  of 
  which 
  the 
  Biological 
  Survey 
  has 
  found 
  

   these 
  insects. 
  Crows 
  and 
  crow 
  blackbirds 
  are 
  particularly 
  useful, 
  and 
  

   an 
  instance 
  is 
  given 
  when 
  one 
  of 
  the 
  latter 
  destroyed 
  in 
  all 
  20 
  grubs 
  

   in 
  about 
  one 
  or 
  two 
  minutes. 
  The 
  skunk 
  is 
  probably 
  the 
  most 
  valuable 
  

   of 
  undomesticated 
  mammals, 
  so 
  that 
  farmers 
  have 
  begun 
  to 
  protect 
  

   it. 
  Of 
  predaceous 
  and 
  parasitic 
  insects 
  the 
  black 
  digger 
  wasp 
  (Tiphia 
  

   inornata, 
  Say), 
  another 
  wasp 
  {Elis 
  sexcinda), 
  and 
  a 
  fly 
  (Pyrgota 
  undata) 
  

  

  (Cll) 
  E 
  

  

  