﻿542 
  Nichols: 
  The 
  vegetation 
  of 
  Connecticut 
  

  

  Herbaceous 
  species 
  

  

  Phalaris 
  arundinacea 
  Vernonia 
  noveboracensis 
  

  

  Spartina 
  Michauxiana 
  Mikania 
  scandens 
  

  

  Elymus 
  spp^ 
  Aster 
  paniculatus 
  

  

  Lobelia 
  cardinalis 
  Ambrosia 
  trifida 
  

  

  Shrubs 
  

  

  Salix 
  lucida 
  Cornus 
  Amomum 
  

  

  I 
  ( 
  

  

  longifolia 
  Clethra 
  alnifolia 
  

  

  Alnus 
  rugosa 
  Cephalanlhus 
  occidentalis 
  

  

  Rosa 
  Carolina 
  Sambucus 
  canadensis 
  

  

  Ilex 
  veriicillata 
  Viburnum 
  dentatum 
  

  

  4. 
  Successional 
  relations 
  along 
  depositing 
  muddy 
  shores 
  

  

  Introductory. 
  — 
  In 
  discussing 
  this 
  phase 
  of 
  the 
  subject 
  attention 
  

   may 
  be 
  confined 
  to 
  the 
  salt 
  marshes, 
  brackish 
  and 
  fresh 
  marshes 
  

  

  ■ 
  

  

  being 
  neglected. 
  Generally 
  speaking, 
  a 
  salt 
  marsh 
  seems 
  to 
  

   originate 
  through 
  the 
  accumulation 
  of 
  silt 
  and 
  organic 
  debris 
  at 
  

   lower 
  levels 
  and 
  the 
  consequent 
  elevation 
  of 
  the 
  substratum 
  to 
  a 
  

  

  r 
  

  

  1 
  

  

  height 
  at 
  which 
  the 
  salt 
  marsh 
  grass 
  is 
  able 
  to 
  establish 
  itself. 
  

   Except 
  for 
  the 
  prominent 
  part 
  played 
  here 
  by 
  the 
  accumulation 
  

   of 
  silt, 
  the 
  manner 
  in 
  which 
  muddy 
  bottoms 
  along 
  the 
  seacoast 
  

   become 
  built 
  up 
  is 
  essentially 
  similar 
  to 
  that 
  in 
  which 
  many 
  lakes 
  

   become 
  filled 
  in 
  during 
  their 
  conversion 
  into 
  swamps 
  (see 
  Nichols, 
  

   '15). 
  There 
  is 
  a 
  close 
  analogy 
  to 
  the 
  early 
  stages 
  in 
  the 
  develop- 
  

   ment 
  of 
  a 
  flood 
  plain 
  (see 
  Nichols, 
  '16), 
  except 
  that, 
  in 
  the 
  present 
  

   case, 
  vegetation 
  plays 
  a 
  more 
  active 
  part 
  and 
  the 
  inorganic 
  debris 
  is 
  

   much 
  finer. 
  Plants 
  assist 
  in 
  the 
  building-up 
  process 
  in 
  two 
  ways: 
  

   first, 
  through 
  their 
  mechanical 
  interference 
  with 
  tidal 
  currents, 
  

   retarding 
  these 
  and 
  causing 
  them 
  to 
  deposit 
  their 
  load 
  of 
  silt; 
  

   second, 
  through 
  the 
  accumulation 
  of 
  their 
  own 
  dead 
  remains. 
  

  

  The 
  apparent 
  succession 
  of 
  plant 
  associations.— 
  Assuming 
  our 
  

   salt 
  marshes 
  to 
  have 
  originated 
  in 
  the 
  manner 
  just 
  suggested, 
  it 
  

   would 
  very 
  naturally 
  be 
  inferred 
  that 
  as 
  the 
  substratum 
  has 
  been 
  

   gradually 
  built 
  up 
  to 
  successively 
  higher 
  elevations 
  and 
  as 
  the 
  

   environmental 
  conditions 
  of 
  the 
  habitat 
  have 
  thereby 
  undergone 
  

   progressive 
  alteration, 
  the 
  rising 
  ground 
  has 
  been 
  successively 
  

   occupied, 
  in 
  order, 
  by 
  the 
  associations 
  (or 
  groups 
  of 
  associations) 
  

   elsewhere 
  described 
  as 
  characteristic 
  of 
  the 
  sublittoral, 
  the 
  lower 
  

   littoral, 
  the 
  midlittoral, 
  and 
  the 
  upper 
  littoral 
  regions. 
  In 
  other 
  

   words, 
  it 
  would 
  seem 
  that 
  the 
  historic 
  succession 
  of 
  plant 
  associa- 
  

  

  