﻿400 
  ANNUAL 
  REPORT 
  SMITHSONIAN 
  INSTITUTION, 
  1943 
  

  

  DEVELOPING 
  A 
  GUAYULE 
  INDUSTRY 
  

  

  In 
  a 
  few 
  years 
  it 
  was 
  plain 
  that 
  the 
  natural 
  supplies 
  of 
  guayule 
  

   were 
  becoming 
  inadequate, 
  and 
  measures 
  for 
  maintaining 
  the 
  indus- 
  

   try 
  began 
  to 
  be 
  considered. 
  Large 
  areas 
  of 
  desert 
  land 
  were 
  acquired 
  

   by 
  some 
  of 
  the 
  rubber 
  companies, 
  and 
  various 
  expedients 
  tested, 
  such 
  

   as 
  protecting 
  young 
  plants 
  and 
  scattering 
  seeds 
  in 
  places 
  that 
  seemed 
  

   most 
  favorable, 
  but 
  with 
  little 
  result. 
  Cultural 
  experiments 
  also 
  were 
  

   undertaken 
  in 
  Mexico 
  and 
  later 
  transferred 
  to 
  southern 
  California, 
  

   near 
  San 
  Diego, 
  in 
  the 
  period 
  of 
  unrest 
  following 
  the 
  revolution 
  of 
  

   1906. 
  The 
  results 
  appeared 
  promising, 
  and 
  in 
  the 
  course 
  of 
  about 
  30 
  

   years 
  the 
  work 
  was 
  carried 
  through 
  the 
  stages 
  of 
  selecting 
  and 
  testing 
  

   many 
  superior 
  varieties, 
  and 
  of 
  developing 
  highly 
  mechanized 
  equip- 
  

   ment 
  for 
  large-scale 
  production 
  and 
  extraction. 
  The 
  proportion 
  of 
  

   rubber 
  in 
  the 
  better 
  strains 
  of 
  guayule 
  is 
  higher 
  than 
  has 
  been 
  deter- 
  

   mined 
  in 
  any 
  other 
  plant, 
  approaching 
  20 
  percent. 
  

  

  Plantings 
  of 
  guayule 
  in 
  the 
  vicinity 
  of 
  Escondido, 
  northeast 
  of 
  San 
  

   Diego, 
  were 
  increased 
  to 
  about 
  400 
  acres, 
  and 
  later, 
  near 
  Tucson, 
  Ariz., 
  

   plantings 
  were 
  expanded 
  to 
  a 
  scale 
  of 
  thousands 
  of 
  acres. 
  There, 
  

   however, 
  conditions 
  proved 
  less 
  favorable 
  for 
  the 
  growth 
  of 
  the 
  

   plants 
  than 
  had 
  been 
  expected, 
  and 
  the 
  undertaking 
  was 
  transferred 
  to 
  

   the 
  Salinas 
  Valley, 
  Calif., 
  in 
  the 
  vicinity 
  of 
  Monterey. 
  There 
  a 
  fac- 
  

   tory 
  large 
  enough 
  to 
  extract 
  the 
  rubber 
  from 
  several 
  thousand 
  acres 
  

   of 
  guayule 
  was 
  built 
  and 
  operated. 
  Grinding, 
  retting, 
  and 
  vacuum 
  

   treatments 
  are 
  necessary, 
  the 
  last 
  to 
  waterlog 
  the 
  wood 
  particles 
  and 
  

   allow 
  all 
  the 
  rubber 
  to 
  float, 
  which 
  completes 
  the 
  separation. 
  The 
  

   expenditures 
  for 
  land, 
  research, 
  and 
  equipment 
  of 
  the 
  three 
  large-scale 
  

   experiments 
  with 
  guayule 
  were 
  credibly 
  reported 
  as 
  approaching 
  

   $2,000,000. 
  

  

  EFFECT 
  OF 
  RIDLEY'S 
  DISCOVERY 
  ON 
  GUAYULE 
  AND 
  CASTILLA 
  

  

  To 
  infer 
  from 
  the 
  history 
  of 
  guayule 
  that 
  the 
  undertaking 
  was 
  de- 
  

   fective 
  or 
  ill-advised 
  would 
  be 
  unfair. 
  The 
  planting 
  of 
  guayule 
  in 
  

   northern 
  Mexico 
  was 
  projected 
  in 
  the 
  same 
  period 
  as 
  the 
  planting 
  of 
  

   Castilla 
  in 
  southern 
  Mexico, 
  and 
  either 
  or 
  both 
  of 
  these 
  undertakings 
  

   might 
  have 
  returned 
  good 
  profits 
  if 
  rubber 
  had 
  not 
  declined 
  below 
  

   a 
  dollar 
  or 
  even 
  50 
  cents 
  a 
  pound. 
  Ridley's 
  discovery 
  in 
  the 
  Orient 
  

   of 
  a 
  continuous 
  method 
  of 
  extracting 
  rubber 
  from 
  the 
  Para 
  rubber 
  

   trees 
  remained, 
  as 
  we 
  have 
  seen, 
  practically 
  unknown 
  and 
  unexplained 
  

   for 
  many 
  years, 
  even 
  after 
  it 
  was 
  being 
  utilized 
  on 
  an 
  extensive 
  scale. 
  

   The 
  Ridley 
  method 
  was 
  possible 
  because 
  the 
  Para 
  rubber 
  tree 
  was 
  

   equipped 
  with 
  a 
  system 
  of 
  connected 
  latex 
  tubes, 
  and 
  because 
  large 
  

   supplies 
  of 
  cheap 
  and 
  skillful 
  labor 
  were 
  available 
  in 
  the 
  East 
  

   Indies. 
  

  

  