﻿438 
  

  

  Childs 
  (L.). 
  Oak 
  Pests 
  — 
  The 
  Oak 
  Twig 
  Girdler 
  (Agrilus 
  poUtiis, 
  Say). 
  

   — 
  Mthhj. 
  Bull. 
  S(a. 
  Co7nmiss. 
  Hortic, 
  Sacramento, 
  Cal., 
  Hi, 
  no. 
  3. 
  

   March 
  1914, 
  pp. 
  150-155, 
  3 
  figs. 
  

  

  The 
  author 
  points 
  out 
  that 
  the 
  live 
  oaks 
  {Quercus 
  agrifolia) 
  through- 
  

   out 
  Cahfornia 
  are 
  subject 
  to 
  many 
  insect 
  pests, 
  of 
  which 
  this 
  paper 
  is 
  

   a 
  prehminary 
  account. 
  The 
  presence 
  of 
  the 
  twig 
  girdler 
  {Agrilus 
  

   jpolitus), 
  a 
  Buprestid 
  beetle, 
  is 
  easily 
  detected 
  on 
  the 
  smaller 
  twigs, 
  and 
  

   where 
  the 
  infestation 
  is 
  severe 
  and 
  of 
  long 
  standing, 
  the 
  vigour 
  of 
  the 
  

   trees 
  is 
  greatly 
  reduced. 
  The 
  larvae 
  generally 
  work 
  upon 
  branches 
  

   which 
  are 
  about 
  the 
  size 
  of 
  a 
  lead 
  pencil 
  and 
  less 
  than 
  \ 
  inch 
  in 
  diameter, 
  

   in 
  which 
  they 
  make 
  spiral 
  galleries 
  destroying 
  the 
  cambium 
  layer 
  

   and 
  killing 
  the 
  twig. 
  The 
  cause 
  of 
  the 
  trouble 
  can 
  easily 
  be 
  deter- 
  

   mined 
  by 
  cutting 
  away 
  the 
  bark 
  of 
  one 
  of 
  the 
  dead 
  twigs, 
  taking 
  

   care 
  not 
  to 
  miss 
  the 
  larva 
  which 
  is 
  slender 
  and 
  will 
  be 
  found 
  at 
  a 
  

   point 
  near 
  the 
  union 
  of 
  the 
  dead 
  and 
  living 
  wood 
  ; 
  the 
  furrow 
  will 
  

   be 
  obvious. 
  Little 
  is 
  known 
  of 
  the 
  different 
  stages 
  of 
  development, 
  

   but 
  from 
  various 
  collecting 
  dates 
  recorded 
  in 
  different 
  years 
  it 
  appears 
  

   that 
  the 
  adults 
  may 
  appear 
  as 
  early 
  as 
  April, 
  but 
  more 
  usually 
  in 
  June. 
  

   The 
  time 
  of 
  appearance 
  of 
  the 
  adult 
  is 
  an 
  important 
  factor 
  in 
  the 
  

   control 
  of 
  the 
  pest, 
  which 
  should 
  be 
  undertaken 
  during 
  autumn 
  and 
  

   winter 
  when 
  the 
  larvae 
  are 
  nearly 
  mature. 
  The 
  best 
  method 
  consists 
  

   of 
  thoroughly 
  cutting 
  out 
  infested 
  parts 
  and 
  burning 
  them 
  at 
  once. 
  

   Observations 
  made 
  at 
  Palo 
  Alto 
  for 
  several 
  years, 
  seem 
  to 
  indicate 
  

   that 
  the 
  beetle 
  does 
  not 
  fly 
  great 
  distances, 
  but 
  for 
  the 
  most 
  part 
  lays 
  

   its 
  eggs 
  in 
  the 
  tree 
  in 
  which 
  it 
  developed. 
  Mention 
  is 
  made 
  of 
  a 
  report 
  

   from 
  S. 
  Nakayama, 
  of 
  Stanford 
  University, 
  on 
  an 
  undetermined 
  

   hymenopterous 
  parasite 
  which 
  attacks 
  the 
  larvae, 
  but 
  little 
  is 
  yet 
  

   known 
  of 
  this 
  insect. 
  

  

  VosLEE 
  (E. 
  J.). 
  Calendar 
  of 
  Insects 
  Pests. 
  — 
  Mthly. 
  Bull 
  Sta. 
  Corn- 
  

   miss. 
  Hortic, 
  Sacramento, 
  Cal., 
  iii, 
  no. 
  3, 
  March 
  1914, 
  pp. 
  162-156. 
  

  

  The 
  citrus 
  thrips 
  causes 
  a 
  leathery 
  distorted 
  growth 
  of 
  the 
  leaves 
  

   and 
  marks 
  the 
  fruit 
  ; 
  another 
  species 
  causes 
  the 
  leaves 
  to 
  become 
  

   yellow 
  and 
  spotted 
  and 
  the 
  fruit-rind 
  silvery 
  ; 
  others 
  feed 
  on 
  parts 
  

   of 
  the 
  flowers. 
  The 
  U.S. 
  Bureau 
  of 
  Entomology 
  recommends 
  the 
  

   following 
  spray 
  : 
  Commercial 
  lime-sulphur 
  (33 
  degrees), 
  2 
  J 
  gallons 
  ; 
  

   black 
  leaf 
  extract, 
  2 
  gallons 
  of 
  2f 
  per 
  cent, 
  or 
  14 
  fluid 
  ounces 
  of 
  40 
  

   per 
  cent., 
  water 
  200 
  gallons. 
  Maintain 
  a 
  strong 
  pressure 
  of 
  about 
  

   175 
  lbs. 
  

  

  Fuller's 
  rose 
  beetle, 
  Pantomorus 
  (Aramigus) 
  fulleri, 
  attacks 
  the 
  new 
  

   foliage 
  of 
  citrus 
  trees 
  and, 
  as 
  it 
  is 
  unable 
  to 
  fly, 
  can 
  be 
  trapped 
  by 
  

   barriers 
  placed 
  round 
  the 
  stems, 
  one 
  t3rpe 
  being 
  a 
  strip 
  of 
  cotton 
  about 
  

   four 
  inches 
  wide, 
  tied 
  with 
  a 
  string 
  on 
  the 
  lower 
  side 
  of 
  the 
  band, 
  

   which 
  is 
  then 
  pulled 
  down 
  over 
  the 
  string 
  so 
  that 
  it 
  extends 
  outwards 
  

   a 
  short 
  distance. 
  Tree 
  tangle-foot 
  may 
  also 
  be 
  used. 
  Diabrotica 
  soror 
  

   is 
  another 
  beetle 
  which 
  attacks 
  the 
  foliage 
  of 
  citrus 
  trees. 
  It 
  may 
  

   be 
  controlled 
  by 
  shaking 
  the 
  beetles 
  into 
  a 
  tarred 
  or 
  oiled 
  screen 
  in 
  

   the 
  early 
  morning, 
  and 
  by 
  poisoning 
  them 
  by 
  spraying 
  with 
  arsenate 
  

   of 
  lead, 
  2 
  lb. 
  to 
  50 
  gallons 
  of 
  water. 
  

  

  The 
  cottony 
  cushion 
  scale, 
  Icerya 
  purchasi, 
  is 
  a 
  pest 
  of 
  Citrus 
  as 
  

   well 
  as 
  of 
  apple, 
  peach, 
  apricot, 
  fig, 
  walnut, 
  acacia, 
  etc., 
  and 
  is 
  usually 
  

  

  