﻿58 
  

  

  suffer. 
  One 
  type 
  of 
  injury 
  which 
  has 
  caused 
  great 
  trouble 
  with 
  the 
  

   English 
  walnuts 
  and 
  pecans, 
  and 
  also 
  with 
  apple 
  trees 
  and 
  has 
  also 
  

   caused 
  trouble 
  with 
  our 
  native 
  red 
  oaks, 
  is 
  freezing 
  when 
  the 
  trees 
  

   are 
  in 
  a 
  non-resistant 
  condition. 
  There 
  is 
  an 
  example 
  of 
  this 
  within 
  

   three 
  minutes' 
  walk 
  of 
  this 
  building. 
  Here 
  are 
  the 
  climatic 
  and 
  

   temperature 
  conditions 
  that 
  bring 
  about 
  disaster, 
  particularly 
  if 
  

   preceded 
  by 
  a 
  dry 
  season. 
  Let 
  us 
  start 
  with 
  a 
  dry 
  season. 
  The 
  

   season 
  of 
  1911 
  was 
  conspicuously 
  dry 
  in 
  this 
  locality 
  and 
  the 
  adja- 
  

   cent 
  states 
  of 
  Virginia, 
  "West 
  Virginia 
  and 
  INIaryland, 
  but 
  about 
  the 
  

   first 
  of 
  September 
  the 
  rains 
  came. 
  Up 
  to 
  that 
  time 
  even 
  the 
  native 
  

   forest 
  trees 
  such 
  as 
  oaks 
  and 
  chestnuts 
  showed 
  the 
  stress 
  of 
  lack 
  of 
  

   moisture 
  very 
  seriously 
  and 
  were 
  somewhat 
  yellow 
  and 
  pale 
  looking, 
  

   mainly 
  from 
  water 
  and 
  nitrogen 
  starvation. 
  When 
  the 
  rains 
  came 
  

   the 
  wilted 
  trees 
  all 
  greened 
  up, 
  every 
  tree 
  in 
  the 
  parks 
  brightened 
  

   up, 
  and 
  we 
  had 
  fine 
  growing 
  conditions 
  until 
  October 
  and 
  no 
  cold 
  

   weather 
  up 
  to 
  New 
  Year's. 
  It 
  was 
  warm 
  that 
  fall 
  and 
  even 
  on 
  New 
  

   Year's 
  daj'' 
  the 
  warmth 
  was 
  noticeable. 
  On 
  the 
  12th 
  of 
  January 
  we 
  

   had 
  the 
  record 
  cold 
  temperature 
  for 
  this 
  locality 
  in 
  the 
  history 
  of 
  

   the 
  w^eather 
  bureau, 
  except 
  one 
  year. 
  We 
  had 
  fifteen 
  or 
  seventeen 
  

   below 
  zero 
  and 
  it 
  was 
  as 
  low 
  as 
  thirty-eight 
  in 
  low 
  spots 
  in 
  the 
  

   Potomac 
  Valley 
  in 
  "West 
  Virginia. 
  Those 
  trees 
  had 
  never 
  been 
  

   fully 
  shocked 
  into 
  winter 
  conditions. 
  The 
  cambium 
  growth 
  and 
  sap 
  

   flow 
  had 
  not 
  been 
  stopped 
  and 
  the 
  physiological 
  changes 
  needed 
  to 
  

   get 
  the 
  trees 
  ready 
  for 
  cold 
  weather 
  had 
  never 
  occurred. 
  They 
  were 
  

   not 
  ready, 
  not 
  onl}^ 
  as 
  to 
  the 
  bark, 
  but 
  in 
  the 
  trunk 
  and 
  wood. 
  The 
  

   result 
  was 
  that 
  the 
  trees 
  were 
  seriously 
  injured, 
  the 
  less 
  matured 
  

   twigs 
  died 
  back, 
  and 
  the 
  trees 
  were 
  frozen 
  on 
  the 
  trunks 
  down 
  to 
  the 
  

   ground 
  line. 
  In 
  the 
  freeze 
  of 
  1904 
  in 
  New 
  York 
  I 
  was 
  surprised 
  to 
  

   find 
  that 
  the 
  peach 
  trees 
  were 
  not 
  all 
  killed. 
  They 
  were 
  frozen 
  

   through 
  and 
  through 
  and 
  yet 
  the 
  trees 
  did 
  not 
  die. 
  The 
  question 
  of 
  

   winter 
  injury 
  hinges 
  not 
  alone 
  on 
  low 
  temperature, 
  but 
  it 
  also 
  

   depends 
  on 
  the 
  condition 
  which 
  the 
  tree 
  has 
  reached 
  when 
  the 
  cold 
  

   strikes 
  it. 
  Now, 
  to 
  tell 
  you 
  still 
  further 
  about 
  what 
  that 
  cold 
  wave 
  

   did, 
  I 
  will 
  ask 
  you 
  to 
  look 
  at 
  that 
  row 
  of 
  red 
  oaks 
  near 
  the 
  Smith- 
  

   sonian 
  which 
  I 
  just 
  alluded 
  to 
  and 
  see 
  the 
  big 
  ribs 
  of 
  dead 
  bark 
  

   where 
  the 
  cambium 
  lajer 
  has 
  been 
  shocked, 
  and 
  checked 
  in 
  other 
  

   places. 
  You 
  will 
  find 
  these 
  trees 
  ribbed 
  and 
  ridged 
  to 
  about 
  half 
  

   way 
  dow^n 
  the 
  row. 
  Those 
  trees 
  are 
  subject 
  to 
  special 
  disadvan- 
  

   tages 
  ; 
  they 
  lack 
  subsoil 
  drainage 
  and 
  they 
  have 
  an 
  excess 
  of 
  manure 
  

   draining 
  do^vn 
  through 
  the 
  paving 
  stones. 
  They 
  have 
  an 
  excess 
  of 
  

   nitrogen 
  and 
  lack 
  of 
  drainage. 
  The 
  subsoil 
  is 
  a 
  heav^^ 
  clay. 
  That 
  

   brings 
  up 
  another 
  thing 
  that 
  I 
  want 
  you 
  to 
  notice 
  in 
  regard 
  to 
  

  

  