﻿3:2 
  

  

  INTRODUCTION 
  TO 
  BOTANY 
  

  

  31. 
  Reproduction 
  

   of 
  producing 
  buds 
  

  

  FIG. 
  24. 
  Vegetative 
  

  

  reproduction 
  of 
  the 
  

  

  sweet 
  potato 
  

  

  The 
  potato 
  was 
  liuried 
  

   in 
  niiiisl 
  sand 
  .-iiid 
  br^aii 
  

   tn 
  s],i-,,ut. 
  that 
  is. 
  to 
  send 
  

   out 
  shoots 
  from 
  adven- 
  

   titious 
  liiuls 
  at 
  various 
  

  

  jioints. 
  Kach 
  si 
  t 
  may 
  

  

  urn\\ 
  into 
  a 
  new 
  plant. 
  

   About 
  half 
  natural 
  si/.r 
  

  

  by 
  means 
  of 
  roots. 
  Roots 
  are 
  often 
  capable 
  

   which 
  may 
  develop 
  into 
  new 
  individuals 
  

   and 
  thus 
  propagate 
  the 
  plant. 
  The 
  sweet 
  

   potato 
  is 
  a 
  good 
  instance 
  of 
  this, 
  each 
  root, 
  

   if 
  buried 
  in 
  moist 
  sand, 
  being 
  capable 
  of 
  

   giving 
  rise 
  to 
  several 
  new 
  plants 
  (fig. 
  24). 
  

   Roses 
  are 
  propagated 
  by 
  root 
  cut 
  t 
  ings, 
  and 
  

   some 
  trees, 
  such 
  as 
  the 
  silver-leaved 
  poplar 
  

   (Pojxiliix) 
  and 
  the 
  black 
  locust 
  (Robinia), 
  

   are 
  very 
  troublesome 
  because 
  of 
  the 
  readi- 
  

   ness 
  with 
  which 
  young 
  sprouts 
  (sometimes 
  

   called 
  suckers) 
  spring 
  up 
  from 
  the 
  roots. 
  

   A 
  considerable 
  colony 
  of 
  these 
  young 
  

   sprouts 
  may 
  often 
  be 
  seen 
  quite 
  surround- 
  

   ing 
  the 
  parent 
  tree 
  and 
  extending 
  many 
  

   feet 
  away 
  from 
  it. 
  Many 
  bad 
  weeds, 
  such 
  

   as 
  the 
  field 
  sorrel 
  (Rumex) 
  and 
  the 
  Canada 
  

   thistle 
  (Cirsiuni), 
  are 
  reproduced 
  by 
  roots. 
  

   In 
  case 
  of 
  desirable 
  plants 
  that 
  can 
  be 
  

   propagated 
  either 
  by 
  pieces 
  of 
  root 
  or 
  by 
  

   seeds, 
  it 
  is 
  generally 
  better 
  to 
  use 
  root 
  

   cuttings, 
  as 
  they 
  will 
  grow 
  much 
  faster. 
  

  

  Among 
  plants 
  that 
  you 
  know, 
  are 
  there 
  

   more 
  instances 
  of 
  useful 
  or 
  of 
  injurious 
  

   kinds 
  that 
  are 
  usually 
  propagated 
  by 
  the 
  

   root? 
  Give 
  examples. 
  

  

  PROBLEMS 
  

  

  1. 
  When 
  actively 
  growing 
  steins 
  are 
  cut 
  off, 
  do 
  they 
  " 
  bleed 
  " 
  on 
  both 
  

   the 
  upper 
  and 
  the 
  lower 
  cut 
  surfaces? 
  Why? 
  

  

  2. 
  I 
  low 
  could 
  an 
  experiment 
  be 
  made 
  to 
  show 
  the 
  exact 
  amount 
  of 
  

   upward 
  pull 
  and 
  of 
  lateral 
  pull 
  which 
  the 
  anchorage 
  of 
  a 
  plant 
  will 
  

  

  resist? 
  

  

  3. 
  What 
  praetieal 
  advantage 
  is 
  taken 
  of 
  tin- 
  powerful 
  anchorage 
  of 
  

   shade 
  trees? 
  

  

  4. 
  Why 
  must 
  swamps 
  be 
  drained 
  before 
  most 
  crops 
  can 
  be 
  grown 
  in 
  

   them? 
  

  

  