﻿52 
  

  

  States 
  and 
  part 
  of 
  the 
  Pacific 
  coast. 
  All 
  this 
  trouble 
  has 
  been 
  

   caused 
  by 
  one 
  little 
  native 
  microbe. 
  Apple 
  culture 
  also, 
  with 
  certain 
  

   varieties, 
  has 
  been 
  seriously 
  interfered 
  with 
  in 
  some 
  sections. 
  

  

  The 
  apple 
  cedar 
  rust 
  is 
  probably 
  the 
  most 
  striking 
  example 
  of 
  a 
  

   native 
  parasite 
  attacking 
  a 
  foreign 
  host 
  that 
  we 
  know 
  of, 
  and 
  

   particularly 
  so 
  as 
  the 
  remarkable 
  evolution 
  in 
  which 
  the 
  parasite 
  

   has 
  adjusted 
  itself 
  to 
  the 
  new 
  host 
  is 
  taking 
  place 
  right 
  now 
  every 
  

   year. 
  The 
  apple 
  cedar 
  rust 
  is 
  becoming 
  a 
  more 
  difficult 
  problem 
  

   clear 
  across 
  the 
  eastern 
  United 
  States 
  to 
  Nebraska. 
  It 
  has 
  occurred 
  

   as 
  a 
  serious 
  disease 
  since 
  1905 
  to 
  1907. 
  As 
  a 
  botanical 
  curiosity 
  we 
  

   have 
  kno^vn 
  it 
  a 
  long 
  time, 
  but 
  as 
  a 
  serious 
  disease, 
  it 
  is 
  very 
  recent, 
  

   and 
  nobody 
  knows 
  yet 
  how 
  serious 
  it 
  is 
  going 
  to 
  be. 
  

  

  We 
  have 
  a 
  very 
  striking 
  example 
  of 
  this 
  introduction 
  of 
  a 
  foreign 
  

   plant 
  and 
  the 
  plant 
  being 
  attacked 
  by 
  a 
  native 
  parasite, 
  in 
  the 
  case 
  

   of 
  the 
  filbert 
  blight, 
  and 
  I 
  am 
  going 
  to 
  take 
  that 
  up 
  later. 
  The 
  

   trouble 
  is 
  that 
  we 
  have 
  brought 
  into 
  the 
  United 
  States 
  a 
  European 
  

   filbert 
  and 
  it 
  has 
  been 
  attacked 
  by 
  a 
  parasite 
  of 
  our 
  wild 
  hazelnuts. 
  

   The 
  disease 
  is 
  very 
  rare 
  and 
  is 
  seldom 
  seen 
  on 
  the 
  wild 
  hazelnut, 
  

   — 
  so 
  rare 
  that 
  it 
  was 
  hardly 
  known 
  by 
  scientific 
  botanists, 
  and 
  yet 
  

   it 
  interferes 
  with 
  filbert 
  culture 
  in 
  the 
  eastern 
  United 
  States 
  and 
  is 
  

   the 
  one 
  thing 
  more 
  than 
  anything 
  else 
  to 
  make 
  filbert 
  culture 
  un- 
  

   profitable. 
  "We 
  have 
  practically 
  the 
  same 
  proposition 
  in 
  the 
  walnut 
  

   bacteriosis, 
  not 
  only 
  in 
  the 
  northeastern 
  United 
  States, 
  but 
  in 
  the 
  

   best 
  walnut 
  districts 
  of 
  California. 
  This 
  bacterial 
  disease 
  which 
  is 
  

   undoubtedly 
  a 
  disease 
  of 
  our 
  native 
  walnuts 
  — 
  probably 
  the 
  native 
  

   black 
  walnut 
  — 
  occurs 
  rather 
  rarely, 
  and 
  so 
  feebly 
  developed 
  as 
  to 
  

   be 
  difficult 
  to 
  find 
  at 
  all 
  on 
  its 
  native 
  host 
  yet 
  it 
  becomes 
  the 
  

   great 
  serious 
  disease 
  of 
  the 
  Old 
  World 
  cultivated 
  walnut. 
  

  

  Now, 
  there 
  again, 
  it 
  is 
  not 
  so 
  much 
  a 
  lack 
  of 
  physiological 
  adapta- 
  

   bility, 
  because 
  the 
  walnut 
  is 
  thoroughly 
  adapted 
  to 
  our 
  Pacific 
  coast. 
  

   I 
  suppose 
  most 
  of 
  you 
  know 
  that 
  east 
  of 
  the 
  Rocky 
  Mountains, 
  east 
  

   of 
  the 
  Great 
  Plains, 
  we 
  have 
  a 
  humid 
  climate 
  and 
  winters 
  more 
  or 
  

   less 
  cold 
  which 
  corresponds, 
  not 
  with 
  western 
  Europe, 
  not 
  with 
  

   Oermany, 
  England, 
  Spain, 
  France 
  and 
  Italy, 
  but 
  with 
  China 
  and 
  

   Japan, 
  with 
  Asia, 
  in 
  its 
  climatic 
  conditions. 
  The 
  result 
  is 
  the 
  

   Chinese 
  and 
  Japanese 
  trees 
  brought 
  to 
  the 
  eastern 
  United 
  States 
  

   grow 
  well 
  but 
  may 
  grow 
  indifferently 
  in 
  California. 
  On 
  the 
  other 
  

   hand, 
  the 
  plants 
  of 
  the 
  Mediterranean, 
  France, 
  Germany, 
  Italy 
  and 
  

   Spain 
  do 
  not, 
  as 
  a 
  rule, 
  thrive 
  when 
  introduced 
  into 
  the 
  eastern 
  

   United 
  States. 
  There 
  are 
  a 
  few 
  exceptions, 
  like 
  the 
  apple 
  and 
  

   perhaps 
  the 
  peach. 
  These 
  are 
  not 
  really 
  natives 
  of 
  western 
  Europe, 
  

   "but 
  have 
  been 
  brought 
  from 
  the 
  interior. 
  They 
  are 
  more 
  like 
  the 
  

  

  