﻿BUDS 
  AND 
  BRANCHES 
  

  

  103 
  

  

  d- 
  

  

  96. 
  The 
  record 
  borne 
  by 
  the 
  twig. 
  In 
  most 
  cases 
  the 
  twig 
  

   bears 
  upon 
  its 
  surface 
  and 
  in 
  its 
  rings 
  of 
  wood 
  a 
  fairly 
  com- 
  

   plete 
  record 
  of 
  the 
  most 
  important 
  events 
  of 
  its 
  life 
  (fig. 
  90). 
  

   Some 
  of 
  the 
  markings 
  on 
  the 
  surface 
  of 
  a 
  

   twig 
  which 
  enable 
  us 
  to 
  make 
  out 
  its 
  his- 
  

   tory 
  are 
  (1) 
  bud-scale 
  scars 
  (from 
  leaf 
  buds 
  ), 
  

   (2) 
  fruit 
  scars, 
  (3) 
  leaf 
  scars. 
  Other 
  mark- 
  

   ings 
  are 
  found 
  which 
  tell 
  less 
  of 
  the 
  life 
  

  

  O 
  

  

  history 
  of 
  the 
  twig 
  than 
  those 
  just 
  enumer- 
  

   ated, 
  but 
  which 
  should 
  also 
  be 
  considered, 
  

   namely, 
  (4) 
  lenticels. 
  

  

  The 
  bud-scale 
  scars, 
  as 
  the 
  name 
  implies, 
  

   are 
  the 
  markings 
  (figs. 
  86 
  and 
  88, 
  b. 
  sc~) 
  left 
  

   by 
  the 
  falling 
  of 
  the 
  scales 
  when 
  the 
  bud 
  

   opened. 
  Plants 
  like 
  geraniums, 
  with 
  naked 
  

   buds, 
  do 
  not 
  show 
  such 
  scars. 
  As 
  the 
  twig 
  

   or 
  branch 
  in 
  most 
  cases 
  is 
  prolonged 
  by 
  the 
  

   growth, 
  spring 
  after 
  spring, 
  of 
  its 
  terminal 
  

   bud, 
  each 
  ring 
  of 
  scars 
  marks 
  the 
  beginning 
  

   of 
  a 
  new 
  season's 
  growth. 
  In 
  many 
  trees 
  it 
  

   is 
  easy 
  to 
  determine 
  the 
  age 
  of 
  twigs 
  or 
  

   branches 
  by 
  counting 
  the 
  number 
  of 
  such 
  

   rings 
  (fig. 
  89). 
  The 
  distance 
  between 
  the 
  

   rings 
  of 
  scars 
  depends 
  upon 
  the 
  rate 
  of 
  condition 
  

  

  lengthwise 
  growth 
  of 
  the 
  shoot 
  ; 
  this 
  varies 
  d> 
  dormant 
  buds 
  ;/s, 
  

  

  all 
  the 
  way 
  from 
  a 
  fraction 
  of 
  an 
  inch 
  to 
  flower-cluster 
  scar. 
  

   The 
  iiiternodes 
  are 
  

  

  ten 
  feet 
  or 
  more 
  per 
  year. 
  

  

  Fi<;. 
  89. 
  A 
  slowly 
  

   grown 
  twig 
  of 
  horse- 
  

   chestnut 
  in 
  winter 
  

  

  1. 
  How 
  many 
  times 
  greater 
  was 
  the 
  rate 
  

   of 
  growth 
  of 
  the 
  central 
  twig 
  in 
  figure 
  88 
  

  

  numbered 
  in 
  succes- 
  

   sion 
  (beginning 
  at 
  

   the 
  bottom) 
  with 
  the 
  

   respective 
  years 
  dur- 
  

  

  thaii 
  the 
  average 
  yearly 
  rate 
  of 
  figure 
  89 
  ? 
  ing 
  which 
  they 
  were 
  

  

  ~ 
  -I 
  TTI 
  < 
  i 
  i 
  formed. 
  One 
  third 
  

  

  2. 
  \v 
  hat 
  was 
  the 
  cause 
  ot 
  this 
  rapid 
  natural 
  size 
  

   growth 
  ? 
  (Examine 
  a 
  horse-chestnut 
  tree.) 
  

  

  3. 
  If 
  the 
  twig 
  in 
  figure 
  89 
  grew 
  unequally 
  in 
  different 
  

   years, 
  what 
  is 
  a 
  probable 
  cause 
  of 
  the 
  fact 
  ? 
  

  

  4. 
  How 
  did 
  the 
  leaves 
  of 
  figure 
  88 
  compare 
  in 
  size 
  with 
  

   those 
  of 
  figure 
  89 
  ? 
  Why 
  ? 
  

  

  