﻿PLANTS 
  OF 
  CHINA 
  — 
  WALKER 
  335 
  

  

  urgent 
  economic 
  problem 
  in 
  China 
  next 
  to 
  that 
  of 
  raising 
  enough 
  

   food 
  for 
  its 
  millions 
  of 
  people. 
  

  

  The 
  vegetation 
  of 
  China 
  varies 
  with 
  respect 
  to 
  the 
  rainfall 
  and 
  

   humidity, 
  which 
  are 
  in 
  turn 
  governed 
  largely 
  by 
  the 
  direction 
  of 
  the 
  

   winds, 
  the 
  seasons, 
  and 
  the 
  location 
  and 
  altitude 
  of 
  the 
  mountains, 
  

   which 
  rise 
  in 
  the 
  west 
  to 
  peaks 
  over 
  22,000 
  feet. 
  The 
  distribution 
  of 
  

   the 
  rainfall 
  throughout 
  the 
  year, 
  the 
  average 
  temperature, 
  the 
  ex- 
  

   tremes 
  of 
  temperature, 
  the 
  character 
  of 
  the 
  soil, 
  and 
  various 
  other 
  

   factors 
  also 
  determine 
  the 
  type 
  of 
  vegetation 
  found 
  in 
  any 
  given 
  area. 
  

   As 
  these 
  factors 
  differ 
  widely 
  throughout 
  the 
  country, 
  so 
  there 
  is 
  

   great 
  variation 
  in 
  the 
  vegetation. 
  

  

  Geographically 
  China 
  can 
  be 
  divided 
  into 
  at 
  least 
  eight 
  floral 
  

   regions 
  as 
  follows 
  (see 
  also 
  map, 
  fig. 
  1, 
  where 
  approximate 
  bound- 
  

   aries 
  are 
  shown) 
  : 
  

  

  1. 
  Northeastern 
  China, 
  including 
  most 
  of 
  Korea 
  and 
  extending 
  

   from 
  northern 
  Manchuria 
  to 
  the 
  great 
  plains 
  of 
  China, 
  marked 
  off 
  

   from 
  the 
  lower 
  Yangtze 
  Valley 
  by 
  the 
  extension 
  of 
  the 
  Tsinling 
  

   Mountains, 
  and 
  reaching 
  westward 
  to 
  the 
  Gobi 
  and 
  Ordos 
  Deserts 
  

   and 
  the 
  loess 
  regions 
  of 
  Shansi. 
  

  

  2. 
  The 
  Gobi 
  Desert 
  region 
  of 
  Mongolia, 
  especially 
  the 
  southern 
  

   part, 
  including 
  the 
  Ordos. 
  

  

  3. 
  The 
  loess 
  region 
  covering 
  eastern 
  Kansu, 
  most 
  of 
  Shensi, 
  and 
  

   part 
  of 
  Shansi. 
  

  

  4. 
  Middle 
  China, 
  comprising 
  the 
  main 
  part 
  of 
  the 
  country 
  from 
  

   the 
  Tsinling 
  Mountains 
  on 
  the 
  north 
  to 
  the 
  Nan 
  Shan 
  on 
  the 
  South 
  

   (that 
  broad 
  range 
  which 
  separates 
  the 
  watersheds 
  of 
  the 
  Si 
  Kiang 
  

   from 
  the 
  Yangtze 
  Kiang) 
  and 
  extending 
  westward 
  across 
  the 
  plateau 
  

   of 
  Yunnan 
  and 
  the 
  basins 
  and 
  lesser 
  mountains 
  of 
  Szechwan 
  to 
  the 
  

   foot 
  of 
  the 
  snow-capped 
  peaks 
  in 
  the 
  west. 
  

  

  5. 
  Tropical 
  and 
  subtropical 
  southern 
  China, 
  including 
  most 
  of 
  

   Kwangsi, 
  all 
  of 
  Kwangtung 
  except 
  the 
  most 
  northern 
  part, 
  coastal 
  

   Fukien 
  and 
  southern 
  Chekiang, 
  and 
  of 
  course 
  Hong 
  Kong 
  and 
  

   Hainan. 
  

  

  6. 
  Southwestern 
  Yunnan, 
  which 
  has 
  the 
  same 
  type 
  of 
  luxuriant 
  

   tropical 
  vegetation 
  as 
  adjacent 
  Burma. 
  

  

  7. 
  The 
  highlands 
  of 
  western 
  China 
  with 
  their 
  deep 
  river 
  gorges 
  

   and 
  snow-capped 
  peaks 
  and 
  corresponding 
  parts 
  of 
  western 
  Szechwan 
  

   and 
  Kansu. 
  

  

  8. 
  The 
  grasslands 
  of 
  eastern 
  Tibet, 
  covering 
  parts 
  of 
  Sikang, 
  Tsing- 
  

   hai, 
  and 
  Kansu. 
  

  

  If 
  Tibet 
  as 
  a 
  whole 
  be 
  included 
  in 
  this 
  greater 
  China 
  area, 
  two 
  more 
  

   floristic 
  regions 
  would 
  be 
  added, 
  namely: 
  (1) 
  the 
  northern 
  plain 
  or 
  

   Chung 
  Tang 
  along 
  with 
  the 
  Tsaidam, 
  the 
  part 
  with 
  internal 
  drainage 
  ; 
  

   and 
  (2) 
  the 
  outer 
  plateau, 
  the 
  part 
  of 
  Tibet 
  drained 
  by 
  several 
  rivers 
  

   which 
  flow 
  through 
  great 
  gorges 
  across 
  the 
  Himalayan 
  Range. 
  

  

  