﻿ni] 
  Special 
  Report 
  No. 
  9 
  : 
  Fungi 
  335 
  

  

  lies 
  just 
  beneath 
  the 
  bark. 
  The 
  heart 
  wood 
  of 
  the 
  tree 
  is 
  dead, 
  

   so 
  that 
  the 
  fungus 
  when 
  it 
  once 
  gets 
  in 
  there 
  can 
  perform 
  its 
  

   destructive 
  work. 
  The 
  living 
  wood, 
  just 
  underneath 
  the 
  bark, 
  

   when 
  it 
  remains 
  unbroken 
  or 
  unharfned 
  forms 
  an 
  impassible 
  bar- 
  

   rier 
  to 
  the 
  entrance 
  of 
  the 
  fungus. 
  

  

  How 
  then 
  did 
  the 
  fungus 
  first 
  get 
  into 
  the 
  heart 
  wood 
  of 
  the 
  

   tree? 
  The 
  photograph 
  tells 
  us 
  something 
  of 
  that. 
  There 
  is 
  an 
  

   old 
  decaying 
  log 
  lying 
  at 
  the 
  foot 
  of 
  the 
  hemlock 
  tree. 
  Twen- 
  

   ty-five 
  or 
  thirty 
  years 
  ago 
  this 
  log 
  was 
  a 
  standing 
  tree. 
  It 
  fell, 
  

   and 
  in 
  its 
  descent 
  it 
  struck 
  the 
  projecting 
  base 
  of 
  the 
  hemlock 
  and 
  

   knocked 
  off 
  the 
  bark 
  and 
  living 
  wood 
  from 
  quite 
  a 
  large 
  area, 
  two 
  

   to 
  three 
  feet 
  in 
  length 
  and 
  a 
  footer 
  more 
  in 
  breadth. 
  The 
  wound 
  

   was 
  so 
  large 
  that 
  it 
  could 
  not 
  heal 
  in 
  time 
  to 
  prevent 
  the 
  entrance 
  

   of 
  the 
  wood 
  destroying 
  organisms. 
  Furthermore, 
  the 
  bruised 
  tis- 
  

   sues 
  would 
  afford 
  a 
  secure 
  lodgment 
  for 
  these 
  germs. 
  So 
  here 
  

   was 
  formed 
  a 
  most 
  favorable 
  infection 
  court, 
  or 
  area. 
  During 
  

   damp 
  weather 
  bacteria 
  and 
  fungus 
  germs, 
  the 
  chief 
  producers 
  of 
  

   the 
  decay 
  of 
  organic 
  matter, 
  lodging 
  here 
  were 
  enabled 
  to 
  get 
  a 
  

   foothold 
  and 
  start 
  the 
  disintegration 
  of 
  the 
  wood. 
  Among 
  them 
  

   were 
  the 
  spores 
  of 
  this 
  Polyporus 
  borealis. 
  These 
  spores 
  pro- 
  

   duced 
  the 
  delicate 
  mycelial 
  threads, 
  and 
  by 
  the 
  ferment 
  action 
  

   of 
  their 
  products 
  these 
  threads 
  gained 
  access 
  to 
  the 
  heart 
  wood, 
  

   where 
  there 
  was 
  an 
  abundance 
  of 
  moisture 
  for 
  growth 
  during 
  

   the 
  entire 
  season. 
  From 
  this 
  point 
  mycelium 
  spread 
  upward 
  

   and 
  outward 
  as 
  it 
  advanced 
  through 
  the 
  tree. 
  

  

  Fruitage. 
  — 
  After 
  a 
  number 
  of 
  years, 
  when 
  the 
  decay 
  had 
  

   extended 
  far 
  up 
  in 
  the 
  tree 
  and 
  a 
  large 
  quantity 
  of 
  the 
  spawn 
  

   or 
  mycelium 
  strands 
  had 
  formed, 
  reaching 
  a 
  large 
  feeding 
  area, 
  

   there 
  was 
  a 
  sufhcient 
  amount 
  of 
  food 
  within 
  reach 
  to 
  form' 
  the 
  

   bracket 
  fruit 
  bodies 
  which 
  can 
  only 
  be 
  formed 
  in 
  the 
  open 
  air. 
  

   This 
  same 
  wound 
  then 
  provided 
  a 
  place 
  of 
  exit 
  for 
  the 
  fruiting 
  

   stage. 
  The 
  spores 
  formed 
  over 
  the 
  honey-combed 
  area 
  are 
  scat- 
  

   tered 
  by 
  the 
  wind, 
  and 
  are 
  ready 
  to 
  infect 
  other 
  trees 
  when 
  an 
  

   opportunity 
  comes. 
  

  

  Hydnum 
  septentrionale. 
  Plate 
  58 
  

  

  Character 
  and 
  distribution 
  . 
  — 
  In 
  Plate 
  58 
  is 
  illustrated 
  another 
  

   fungus 
  growing 
  on 
  a 
  living 
  sugar 
  maple 
  tree. 
  This 
  is 
  also 
  one 
  

   of 
  the 
  bracket 
  or 
  shelving 
  fungi. 
  Its 
  natural 
  size 
  is 
  about 
  eight 
  

  

  