﻿340 
  ANNUAL 
  REPORT 
  SMITHSONIAN 
  INSTITUTION, 
  1943 
  

  

  from 
  a 
  few 
  inches 
  to 
  several 
  hundred 
  feet 
  and 
  covers 
  a 
  large 
  area 
  in 
  

   Kansu, 
  Shensi, 
  and 
  Shansi. 
  (For 
  approximate 
  location, 
  see 
  map, 
  fig. 
  1.) 
  

   The 
  climate 
  of 
  this 
  area 
  is 
  essentially 
  continental, 
  and 
  the 
  vegetation 
  

   is 
  scarcely 
  better 
  off 
  for 
  quantity 
  of 
  moisture 
  than 
  is 
  that 
  in 
  the 
  Gobi 
  

   and 
  Ordos 
  Deserts. 
  Most 
  of 
  the 
  rain 
  comes 
  in 
  July 
  and 
  August. 
  How- 
  

   ever, 
  the 
  fine 
  loess 
  soil 
  holds 
  by 
  capillarity 
  the 
  water 
  which 
  it 
  does 
  

   receive 
  and 
  raises 
  it 
  from 
  the 
  water 
  table 
  to 
  heights 
  where 
  deep-rooted 
  

   plants 
  can 
  reach 
  and 
  use 
  it. 
  The 
  loess 
  itself 
  is 
  highly 
  fertile, 
  and 
  good 
  

   crops 
  of 
  shallow-rooted 
  plants 
  can 
  be 
  grown 
  where 
  sufficient 
  water 
  

   can 
  be 
  brought 
  to 
  the 
  fields. 
  Thus, 
  the 
  loess 
  region 
  is 
  better 
  provided 
  

   with 
  vegetation 
  than 
  is 
  the 
  desert, 
  but 
  yet, 
  as 
  compared 
  with 
  the 
  rest 
  

   of 
  China, 
  the 
  plant 
  cover 
  is 
  woefully 
  thin. 
  In 
  composition 
  this 
  vege- 
  

   tation 
  is 
  closely 
  related 
  to 
  that 
  of 
  central 
  Asia 
  and 
  the 
  desert 
  regions. 
  

   Jujubes, 
  poplars, 
  elms, 
  and 
  willows 
  constitute 
  the 
  principal 
  woody 
  

   plants. 
  There 
  are 
  no 
  endemics. 
  In 
  all 
  probability 
  forests 
  grew 
  here 
  

   in 
  former 
  times, 
  but 
  scarcely 
  any 
  remnants 
  are 
  left 
  today. 
  As 
  wood 
  is 
  

   lacking 
  there 
  is 
  little 
  fuel 
  and 
  practically 
  no 
  timber 
  for 
  building, 
  but 
  

   the 
  happy 
  circumstance 
  that 
  the 
  loess 
  deposits 
  can 
  be 
  tunneled 
  into 
  

   without 
  caving 
  in 
  enables 
  whole 
  villages 
  to 
  be 
  carved 
  out 
  of 
  the 
  cliffs, 
  

   and 
  wood 
  need 
  be 
  used 
  only 
  for 
  doors, 
  window 
  frames, 
  furniture, 
  and 
  

   farm 
  implements. 
  As 
  the 
  walls 
  of 
  these 
  cave 
  dwellings 
  conduct 
  little 
  

   heat, 
  the 
  houses 
  are 
  cool 
  in 
  summer 
  and 
  warm 
  in 
  winter. 
  

  

  The 
  great 
  problem 
  in 
  the 
  loess 
  region 
  is 
  that 
  of 
  erosion 
  by 
  water 
  and 
  

   by 
  wind, 
  aided 
  by 
  violent 
  earthquakes. 
  With 
  such 
  unstable 
  conditions 
  

   prevailing 
  and 
  with 
  the 
  inhabitants 
  scraping 
  the 
  hillsides 
  for 
  every 
  

   possible 
  bit 
  of 
  fuel, 
  a 
  thriving 
  native 
  vegetation 
  could 
  hardly 
  be 
  

   expected. 
  

  

  MIDDLE 
  CHINA 
  

  

  The 
  bulk 
  of 
  the 
  flora 
  which 
  is 
  commonly 
  thought 
  of 
  as 
  character- 
  

   istically 
  Chinese 
  is 
  found 
  in 
  the 
  great 
  basin 
  or 
  basins 
  of 
  the 
  Yangtze 
  

   River 
  and 
  its 
  tributaries. 
  This 
  is 
  the 
  largest 
  floral 
  province 
  in 
  China 
  

   and 
  extends 
  from 
  the 
  Tsinling 
  Mountains, 
  southern 
  Honan, 
  and 
  north- 
  

   central 
  Anhwei 
  and 
  Kiangsu 
  on 
  the 
  north 
  to 
  the 
  northern 
  border 
  of 
  

   Kwangsi, 
  the 
  northern 
  portion 
  of 
  Kwangtung, 
  and 
  southern 
  Fukien, 
  

   and 
  from 
  the 
  coast 
  of 
  the 
  China 
  Sea, 
  except 
  parts 
  of 
  Fukien 
  and 
  

   Chekiang, 
  westward 
  to 
  the 
  lower 
  parts 
  of 
  the 
  high 
  snow-clad 
  moun- 
  

   tains 
  in 
  the 
  west. 
  The 
  plateau 
  of 
  Yunnan 
  lies 
  within 
  this 
  floral 
  area. 
  

   The 
  Tsinling 
  Range 
  on 
  the 
  north 
  effectively 
  cuts 
  off 
  the 
  cold 
  winds 
  of 
  

   central 
  Asia 
  and 
  permits 
  the 
  vegetation 
  toward 
  the 
  south 
  to 
  thrive 
  

   under 
  the 
  more 
  benign 
  influence 
  of 
  the 
  summer 
  monsoon 
  from 
  the 
  

   southeast. 
  Hence, 
  in 
  contrast 
  with 
  the 
  cool-temperate 
  flora 
  of 
  north- 
  

   eastern 
  China 
  and 
  the 
  desert 
  vegetation 
  of 
  the 
  Gobi 
  and 
  loess 
  regions, 
  

   we 
  find 
  in 
  middle 
  China 
  a 
  warm-temperate 
  or 
  even, 
  in 
  places, 
  a 
  sub- 
  

   tropical 
  vegetation. 
  It 
  varies, 
  of 
  course, 
  with 
  the 
  distance 
  from 
  the 
  

  

  