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  REPORT 
  UNITED 
  STATES 
  ENTOMOLOGICAL 
  COMMISSION. 
  

  

  In 
  Arizona 
  the 
  fertile 
  area 
  is 
  still 
  farther 
  circumscribed, 
  being 
  not 
  

   more 
  than 
  3,000 
  square 
  miles. 
  It 
  is 
  found 
  only 
  on 
  the 
  higher 
  plateaus, 
  

   the 
  Uinkaret, 
  the 
  Paria, 
  and 
  Sand 
  Dune, 
  in 
  the 
  valley 
  of 
  the 
  Rio 
  de 
  

   Chelly, 
  and 
  in 
  Nine 
  Mile 
  Valley. 
  

  

  In 
  Nevada 
  the 
  area 
  is 
  about 
  the 
  same, 
  and 
  is 
  nearly 
  all 
  confined 
  to 
  

   the 
  mountain 
  ranges 
  in 
  the 
  northeast 
  and 
  a 
  few 
  valleys 
  on 
  the 
  northern 
  

   border, 
  such 
  as 
  that 
  of 
  Quinn's 
  River. 
  

  

  It 
  would 
  seem, 
  therefore, 
  that 
  of 
  the 
  400,000 
  square 
  miles 
  embraced 
  

   in 
  the 
  Permanent 
  Region, 
  but 
  about 
  177,000, 
  or 
  about 
  one-third 
  of 
  the 
  

   whole, 
  is 
  of 
  such 
  a 
  character 
  as 
  to 
  permit 
  excessive 
  multiplication 
  of 
  the 
  

   locust. 
  Some 
  19,000 
  are 
  contained 
  in 
  Washington 
  Territory, 
  Oregon, 
  

   and 
  Idaho, 
  where 
  the 
  movements 
  of 
  the 
  locusts 
  are 
  neither 
  so 
  regular 
  

   nor 
  controlled 
  by 
  the 
  same 
  laws 
  as 
  are 
  those 
  of 
  the 
  hordes 
  which 
  breed 
  

   in 
  the 
  Northwest, 
  east 
  of 
  the 
  mountains. 
  It 
  is 
  noticeable 
  also 
  that 
  in 
  

   British 
  America 
  there 
  is 
  more 
  land 
  favorable 
  to 
  permanent 
  breeding 
  

   and 
  excessive 
  multiplication 
  than 
  in 
  all 
  the 
  rest 
  of 
  the 
  Permanent 
  Region, 
  

   and 
  that 
  the 
  country 
  in 
  Montana 
  just 
  south 
  of 
  the 
  boundary 
  line 
  fur- 
  

   nishes 
  the 
  next 
  largest 
  amount. 
  

  

  We 
  will 
  therefore 
  at 
  once 
  consider 
  in 
  how 
  far 
  each 
  of 
  the 
  preventive 
  

   measures 
  is 
  practicable 
  in 
  this 
  plains 
  area, 
  and 
  the 
  results 
  that 
  may 
  be 
  

   expected 
  from 
  liberal 
  government 
  support 
  of 
  either. 
  

  

  1. 
  Encouragement 
  to 
  settlement. 
  — 
  That 
  every 
  encouragement 
  

   to 
  the 
  settlement 
  of 
  the 
  Northwest 
  should 
  be 
  given 
  we 
  have 
  endeavored 
  

   to 
  show 
  in 
  Chapter 
  II. 
  Aside 
  from 
  the 
  fact 
  now 
  generally 
  conceded, 
  

   and 
  which 
  the 
  experience 
  of 
  the 
  last 
  quarter 
  of 
  a 
  century 
  seems 
  to 
  demon- 
  

   strate, 
  that 
  the 
  climate 
  is 
  materially 
  modified 
  and 
  rendered 
  more 
  humid 
  

   by 
  settlement 
  and 
  cultivation, 
  it 
  is 
  also 
  a 
  self-evident 
  fact 
  that 
  in 
  pro- 
  

   portion 
  as 
  the 
  farming 
  population 
  increases 
  and 
  pushes 
  into 
  the 
  region 
  

   where 
  the 
  locust 
  permanently 
  breeds, 
  in 
  that 
  proportion 
  will 
  the 
  extent 
  

   of 
  those 
  permanent 
  breeding 
  grounds 
  be 
  reduced 
  by 
  man's 
  necessary 
  

   efforts 
  in 
  self-protection. 
  

  

  Compared 
  to 
  the 
  excessive 
  injury 
  from 
  locusts 
  which 
  formerly 
  pre- 
  

   vailed 
  in 
  Central 
  Europe, 
  there 
  has 
  been 
  great 
  freedom 
  from 
  their 
  ravages 
  

   during 
  the 
  past 
  century, 
  a 
  fact 
  evidently 
  due 
  in 
  large 
  part, 
  if 
  not 
  entirely, 
  

   to 
  the 
  increase 
  of 
  population 
  and 
  settlement. 
  With 
  a 
  dense 
  population 
  

   it 
  is 
  easy 
  to 
  adopt 
  preventive 
  measures 
  by 
  destroying 
  the 
  eggs 
  and 
  young 
  

   of 
  invading 
  swarms. 
  So 
  also 
  in 
  Utah 
  the 
  injury 
  and 
  fear 
  of 
  injury 
  on 
  

   the 
  part 
  of 
  the 
  Mormons 
  have 
  decreased 
  in 
  proportion 
  as 
  population 
  and 
  

   settlement 
  increased. 
  

  

  The 
  belief 
  is 
  very 
  general 
  among 
  those 
  who 
  have 
  studied 
  the 
  subject 
  

   that 
  the 
  planting 
  of 
  tree 
  belts 
  and 
  forests 
  tends 
  greatly 
  to 
  ameliorate 
  a 
  

   dry 
  climate 
  by 
  causing 
  rain 
  precipitation 
  where 
  otherwise 
  the 
  clouds 
  

   would 
  pass 
  over 
  and 
  away, 
  as 
  well 
  as 
  by 
  more 
  nearly 
  equalizing 
  the 
  

   normal 
  annual 
  rainfall, 
  which, 
  on 
  our 
  plains, 
  is 
  generally 
  borne 
  to 
  earth 
  

   in 
  torrential 
  storms, 
  which 
  do 
  comparatively 
  little 
  good. 
  We 
  have 
  no 
  

   doubt 
  but 
  that 
  the 
  belief 
  is 
  well 
  founded, 
  for 
  careful 
  researches 
  carried 
  

  

  