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  is 
  present. 
  Then 
  by 
  cutting: 
  into 
  the 
  bark 
  a 
  littk\ 
  instead 
  of 
  the 
  normal 
  

   buff 
  or 
  yeHowish 
  tint 
  of 
  the 
  fresli 
  elean 
  bark, 
  we 
  get, 
  when 
  the 
  disease 
  

   is 
  present, 
  a 
  rather 
  uiotth'd 
  effect, 
  varying 
  from 
  a 
  brownish 
  to 
  lighter 
  

   or 
  even 
  darker. 
  There 
  is 
  a 
  peculiar 
  fan-like 
  effect 
  to 
  this 
  mycelium 
  

   which 
  penetrates 
  the 
  bark, 
  so 
  that 
  by 
  shavii\g 
  off 
  the 
  surface 
  of 
  the 
  bark, 
  

   you 
  get 
  this 
  mottled 
  appearance, 
  which 
  gives 
  you 
  another 
  means 
  of 
  

   identifying 
  the 
  disease. 
  So 
  we 
  look 
  for 
  the 
  danger 
  signals, 
  and 
  then 
  

   look 
  for 
  the 
  meaning 
  of 
  the 
  danger 
  signals. 
  If 
  we 
  find 
  those 
  two 
  things, 
  

   the 
  pustules 
  and 
  the 
  mottled 
  mycelium, 
  we 
  can 
  very 
  safely 
  say 
  that 
  

   this 
  disease 
  is 
  present. 
  

  

  There 
  are 
  a 
  few 
  fungi 
  which 
  closely 
  resemble 
  this 
  chestnut 
  disease 
  

   in 
  general 
  appearance, 
  but 
  they 
  are 
  not 
  very 
  common, 
  and 
  are 
  not 
  con- 
  

   fused 
  with 
  the 
  disease, 
  as 
  a 
  rule, 
  when 
  j^ou 
  get 
  the 
  lens 
  on 
  them. 
  

  

  In 
  regard 
  to 
  the 
  experiments 
  for 
  the 
  control 
  of 
  the 
  disease, 
  I 
  want 
  

   to 
  say 
  a 
  few 
  words. 
  As 
  far 
  back 
  as 
  1907, 
  the 
  United 
  States 
  Depart- 
  

   ment 
  of 
  Agriculture 
  began 
  experiments 
  on 
  certain 
  experimental 
  plots, 
  

   particularly 
  in 
  Long 
  I.sland 
  near 
  the 
  region 
  where 
  the 
  earliest 
  cases 
  of 
  

   this 
  disease 
  were 
  known, 
  to 
  see 
  if 
  it 
  could 
  be 
  controlled 
  on 
  individual 
  

   trees 
  after 
  they 
  had 
  become 
  infected. 
  Later, 
  experiments 
  were 
  under- 
  

   taken 
  along 
  the 
  same 
  line 
  in 
  Lancaster 
  County, 
  Pennsylvania. 
  Spray- 
  

   ing 
  was 
  tried, 
  although 
  there 
  was 
  no 
  idea 
  that 
  it 
  would 
  be 
  of 
  any 
  use, 
  

   because 
  the 
  vegetative 
  stage 
  of 
  this 
  fungus 
  is 
  running 
  through 
  the 
  in- 
  

   terior 
  of 
  the 
  bark, 
  where 
  no 
  spray 
  could 
  reach 
  it. 
  Thus 
  spraying 
  was 
  

   found 
  to 
  be 
  of 
  no 
  use 
  whatever. 
  Then 
  the 
  operation 
  of 
  cutting 
  out 
  

   the 
  disease 
  was 
  tried. 
  Where 
  the 
  diseased 
  spot 
  appeared, 
  it 
  was 
  cut 
  out 
  

   with 
  a 
  gouge. 
  Then 
  the 
  exposed 
  area 
  was 
  covered 
  in 
  various 
  ways 
  with 
  

   antisptics. 
  

  

  This 
  gave, 
  for 
  a 
  year 
  or 
  two, 
  very 
  promising 
  results, 
  but 
  about 
  the 
  

   third 
  year 
  the 
  disease 
  appeared 
  to 
  get 
  over 
  on 
  to 
  the 
  margin, 
  where 
  

   it 
  had 
  been 
  cut. 
  This 
  led 
  to 
  the 
  later 
  discovery 
  that 
  the 
  disease 
  had 
  

   been 
  running 
  in 
  the 
  wood, 
  as 
  we 
  had 
  previously 
  suspected. 
  So 
  the 
  

   cutting 
  out 
  of 
  the 
  bark 
  alone 
  is 
  not 
  sufficient. 
  This 
  j^ear 
  cutting 
  has 
  

   been 
  done 
  so 
  as 
  to 
  include 
  a 
  portion 
  of 
  the 
  sap 
  wood. 
  

  

  There 
  is 
  just 
  one 
  other 
  topic 
  which 
  I 
  want 
  to 
  allude 
  to. 
  That 
  is 
  in 
  

   regard 
  to 
  the 
  immunity 
  question. 
  It 
  has 
  been 
  found 
  that 
  this 
  disease 
  

   attacks 
  the 
  commcm 
  native 
  chestnut, 
  the 
  chinquapin, 
  the 
  various 
  culti- 
  

   vated 
  European 
  chestnuts, 
  but 
  very 
  rarely 
  the 
  Japanese. 
  In 
  regard 
  to 
  

   this 
  point, 
  I 
  hope 
  that 
  Doctor 
  Morris 
  will 
  tell 
  us 
  something 
  about 
  his 
  

   experiments 
  on 
  the 
  breeding 
  of 
  chestnuts 
  with 
  the 
  idea 
  of 
  producing 
  a 
  

   new 
  and 
  immune 
  variety. 
  

  

  You 
  will 
  understand 
  that 
  I 
  have 
  just 
  made 
  an 
  outline 
  of 
  this 
  

   disease, 
  and 
  I 
  hope 
  that, 
  if 
  there 
  are 
  any 
  questions 
  to 
  be 
  asked, 
  you 
  will 
  

   make 
  them 
  easy, 
  so 
  that 
  I 
  can 
  answer 
  them. 
  

  

  I 
  

  

  