﻿SILVICCLTURAL 
  NOTES. 
  

  

  35 
  

  

  Table 
  No. 
  11. 
  — 
  Per 
  cent 
  of 
  sapwood 
  in 
  the 
  merchantable 
  contents 
  of 
  Shortleaf 
  and 
  

   Loblolly 
  Pine, 
  for 
  diameters 
  from 
  24 
  to 
  32 
  inches, 
  breasthigh. 
  

  

  Diameter 
  

   breasthigh. 
  

  

  Shortleaf. 
  

  

  Loblolly. 
  

  

  Inches. 
  

  

  Per 
  cent. 
  

  

  Per 
  cent. 
  

  

  24 
  

  

  55. 
  4 
  

  

  76.0 
  

  

  25 
  

  

  53.4 
  

  

  72.5 
  

  

  26 
  

  

  51.4 
  

  

  68.9 
  

  

  27 
  

  

  49.9 
  

  

  65.2 
  

  

  28 
  

  

  48.7 
  

  

  61.3 
  

  

  29 
  

  

  47.7 
  

  

  57.3 
  

  

  30 
  

  

  47.0 
  

  

  53.1 
  

  

  31 
  

  

  46.3 
  

  

  48.9 
  

  

  32 
  

  

  45.8 
  

  

  44.5 
  

  

  The 
  growth 
  of 
  the 
  Loblolly 
  Pine 
  can 
  best 
  be 
  understood 
  by 
  a 
  study 
  

   of 
  the 
  curves 
  of 
  the 
  various 
  diagrams. 
  Most 
  of 
  these 
  will 
  be 
  found 
  in 
  

   the 
  figures 
  already 
  given 
  for 
  Shortleaf 
  Pine. 
  The 
  curves 
  for 
  both 
  

   species 
  are 
  shown 
  on 
  the 
  same 
  diagram, 
  that 
  the 
  two 
  may 
  be 
  more 
  

   readily 
  c< 
  unpaivd. 
  

  

  R, 
  f, 
  it',<, 
  i, 
  ,,f 
  <i't<- 
  t" 
  d'niimtir. 
  — 
  (See 
  fig. 
  5.) 
  The 
  curve 
  for 
  Loblolly 
  

   Pine 
  here 
  shows 
  a 
  much 
  more 
  rapid 
  growth 
  than 
  that 
  of 
  the 
  Shortleaf. 
  

   For 
  the 
  first 
  one 
  hundred 
  years 
  the 
  average 
  time 
  required 
  to 
  grow 
  1 
  

   inch 
  is 
  four 
  and 
  one-half 
  years. 
  If 
  the 
  cutting 
  limit 
  be 
  placed 
  at 
  12 
  

   inches, 
  it 
  will 
  be 
  seen 
  that 
  Loblolly 
  reaches 
  a 
  merchantable 
  size 
  when 
  

   44 
  years 
  old, 
  or 
  eighteen 
  years 
  earlier 
  than 
  the 
  Shortleaf. 
  

  

  lief 
  of 
  Ion 
  of 
  age 
  to 
  fieight. 
  — 
  (See 
  tig. 
  (5.) 
  The 
  height 
  growth 
  for 
  

   Loblolly 
  is 
  rapid 
  and 
  very 
  uniform 
  for 
  nearly 
  forty 
  years. 
  After 
  this 
  

   age 
  the 
  rate 
  gradually 
  diminishes. 
  For 
  the 
  first 
  one 
  hundred 
  years 
  

   the 
  yearly 
  average 
  growth 
  in 
  height 
  is 
  L.04 
  feet. 
  As 
  can 
  be 
  seen 
  from 
  

   the 
  two 
  curves, 
  there 
  is 
  very 
  little 
  difference 
  in 
  the 
  height 
  growth 
  of 
  

   the 
  two 
  species 
  for 
  the 
  first 
  twenty 
  years. 
  

  

  Relation 
  of 
  age 
  to 
  merchantable 
  contents. 
  — 
  (See 
  fig. 
  7.) 
  The 
  volume 
  

   curve 
  here 
  given 
  for 
  Loblolly 
  Pine 
  is 
  seen 
  to 
  be 
  very 
  nearly 
  a 
  straight 
  

   line. 
  The 
  rate 
  of 
  increase 
  in 
  merchantable 
  contents 
  is 
  remarkably 
  

   uniform. 
  The 
  upper 
  portion 
  of 
  this 
  line 
  is 
  dotted, 
  because 
  so 
  very 
  few 
  

   Loblollies 
  over 
  160 
  years 
  of 
  age 
  were 
  analyzed 
  that 
  the 
  results 
  can 
  

   not 
  be 
  accepted 
  as 
  conclusive. 
  It 
  is 
  probable 
  that 
  in 
  practice 
  the 
  

   actual 
  contents 
  of 
  the 
  older 
  trees 
  would 
  be 
  somewhat 
  less 
  than 
  is 
  here 
  

   shown. 
  Between 
  the 
  ages 
  of 
  44 
  (when 
  the 
  Loblolly 
  reaches 
  a 
  diameter 
  

   of 
  12 
  inches) 
  and 
  100 
  years, 
  the 
  average 
  yearly 
  increase 
  in 
  merchant- 
  

   able 
  contents 
  is 
  9.28 
  board 
  feet 
  per 
  tree. 
  

  

  Relation 
  hitii'i, 
  -it 
  diameter, 
  total 
  /night, 
  merehil 
  ntidil 
  '< 
  length, 
  ei'mi'li 
  

  

  length, 
  and 
  clear 
  length. 
  — 
  (See 
  fig. 
  9.) 
  In 
  trees 
  from 
  15 
  to 
  30 
  inches 
  

   in 
  diameter 
  the 
  merchantable 
  length 
  increases 
  quite 
  regularly 
  as 
  the 
  

   diameter 
  becomes 
  larger, 
  but 
  in 
  trees 
  above 
  30 
  inches 
  the 
  length 
  of 
  

  

  