﻿292 
  REPORT 
  UNITED 
  STATES 
  ENTOMOLOGICAL 
  COMMISSION. 
  

  

  Mountain 
  Valley 
  and 
  Huerfano 
  Park. 
  West 
  of 
  the 
  Sangre 
  de 
  Cristo 
  

   Eange 
  lies 
  the 
  large 
  valley 
  of 
  San 
  Luis, 
  beyond 
  which 
  is 
  the 
  broad 
  and 
  

   complex 
  group 
  known 
  as 
  the 
  San 
  Juan 
  Mountains. 
  These 
  ranges 
  are 
  

   all 
  covered 
  with 
  forests 
  to 
  the 
  timber 
  line. 
  The 
  Wet 
  Mountain 
  Valley 
  

   is 
  timbered 
  except 
  in 
  the 
  lower 
  part 
  near 
  the 
  Arkansas 
  River, 
  where 
  the 
  

   plateaus, 
  into 
  which 
  it 
  develops, 
  are 
  well 
  grassed. 
  The 
  Huerfano 
  Park 
  

   has 
  a 
  very 
  similar 
  vegetation, 
  being 
  timbered 
  near 
  the 
  divide 
  and 
  on 
  the 
  

   minor 
  ridges, 
  while 
  grasses 
  cover 
  the 
  lower 
  parts. 
  

  

  The 
  San 
  Luis 
  Valley, 
  which 
  contains 
  the 
  upper 
  course 
  of 
  the 
  Eio 
  

   Grande, 
  is 
  a 
  long 
  valley, 
  extending 
  from 
  Poncho 
  Pass 
  down 
  into 
  New 
  

   Mexico. 
  It 
  has 
  a 
  length 
  of 
  about 
  140 
  miles, 
  a 
  maximum 
  width 
  of 
  fifty, 
  

   and 
  an 
  average 
  width 
  of 
  35 
  or 
  40 
  miles. 
  Its 
  area 
  is 
  not 
  far 
  from 
  5,300 
  

   square 
  miles, 
  of 
  which 
  about 
  two 
  thirds 
  is 
  in 
  Colorado 
  and 
  the 
  balance 
  

   in 
  New 
  Mexico. 
  Its 
  surface 
  is 
  almost 
  as 
  level 
  as 
  a 
  billiard 
  table. 
  In 
  

   the 
  northern 
  part 
  the 
  growth 
  is 
  bunch-grass. 
  As 
  we 
  proceed 
  southward 
  

   it 
  changes 
  very 
  gradually 
  to 
  sage, 
  which 
  in 
  turn 
  becomes 
  more 
  and 
  

   more 
  stunted, 
  and 
  in 
  the 
  southern 
  part 
  of 
  the 
  valley 
  the 
  vegetation 
  is 
  very 
  

   scanty, 
  excepting 
  at 
  the 
  bases 
  of 
  the 
  ranges 
  on 
  the 
  sides. 
  The 
  soil, 
  too, 
  

   undergoes 
  a 
  corresponding 
  change 
  from 
  a 
  gravelly 
  soil 
  at 
  the 
  northern 
  

   end 
  and 
  at 
  the 
  bases 
  of 
  the 
  mountains 
  on 
  the 
  sides. 
  Farther 
  down 
  the 
  

   valley, 
  about 
  Sawatch 
  Creek, 
  the 
  soil 
  becomes 
  a 
  stiff 
  adobe 
  clay, 
  and 
  yet 
  

   farther 
  down 
  the 
  valley 
  it 
  becomes 
  very 
  sandy. 
  In 
  some 
  places 
  along 
  

   the 
  eastern 
  side 
  of 
  the 
  valley 
  the 
  sand 
  has 
  heaped 
  up 
  in 
  drifts 
  or 
  dunes. 
  

   This 
  is 
  notably 
  the 
  case 
  near 
  the 
  Music 
  and 
  Mosca 
  Passes. 
  The 
  sand 
  

   begins 
  near 
  the 
  latitude 
  of 
  the 
  point 
  where 
  the 
  Eio 
  Grande 
  enters 
  the 
  

   valley, 
  and 
  extends 
  down 
  to 
  its 
  southern 
  end. 
  

  

  There 
  is 
  quite 
  a 
  large 
  area 
  of 
  marsh 
  and 
  semi-marsh 
  in 
  the 
  northern 
  

   portion 
  of 
  the 
  valley. 
  San 
  Luis 
  and 
  Sawatch 
  Creeks 
  entering 
  the 
  val- 
  

   ley 
  near 
  its 
  northern 
  end, 
  join 
  and 
  flow 
  down 
  the 
  valley 
  near 
  its 
  eastern 
  

   border, 
  and 
  sink 
  in 
  the 
  San 
  Luis 
  Lakes, 
  near 
  Mosca 
  Pass. 
  Their 
  course 
  

   in 
  the 
  valley, 
  and 
  especially 
  below 
  their 
  point 
  of 
  junction, 
  is 
  sluggish 
  and 
  

   accompanied 
  by 
  a 
  broad 
  belt 
  of 
  marsh 
  and 
  of 
  land 
  naturally 
  irrigated. 
  

   About 
  the 
  lakes 
  this 
  area 
  is 
  much 
  enlarged. 
  

  

  The 
  San 
  Juan 
  Mountains 
  contain 
  no 
  valleys 
  of 
  any 
  extent. 
  Baker's 
  

   Park, 
  an 
  area 
  of 
  possibly 
  half 
  a 
  dozen 
  square 
  miles, 
  is 
  the 
  only 
  bit 
  of 
  

   flat 
  country 
  to 
  be 
  found 
  among 
  them, 
  except 
  among 
  their 
  lower 
  spurs, 
  

   which 
  will 
  be 
  noticed 
  farther 
  on, 
  under 
  the 
  head 
  of 
  the 
  Plateau 
  area. 
  

  

  Proceeding 
  southward 
  into 
  New 
  Mexico, 
  we 
  find 
  the 
  lower 
  limit 
  of 
  

   timber 
  crowded 
  higher 
  and 
  higher 
  up 
  on 
  the 
  mountains, 
  so 
  that, 
  on 
  the 
  

   lower 
  ranges 
  of 
  the 
  southern 
  part 
  of 
  the 
  State, 
  there 
  is 
  no 
  timber 
  what- 
  

   ever. 
  

  

  The 
  low 
  range 
  of 
  the 
  Eatons 
  on 
  the 
  boundary 
  between 
  Colorado 
  and 
  

   New 
  Mexico 
  is 
  well 
  timbered, 
  though 
  grasses 
  extend 
  well 
  up 
  its 
  slopes. 
  

   The 
  Sangre 
  de 
  Cristo 
  Eange 
  is 
  covered 
  with 
  forests 
  to 
  its 
  end, 
  near 
  San- 
  

   ta 
  F6, 
  and 
  the 
  Sandia 
  Mountains, 
  a 
  short 
  group 
  which 
  continues 
  its 
  

   course 
  for 
  a 
  few 
  miles 
  southward, 
  are 
  also 
  well 
  timbered. 
  East 
  of 
  the 
  

  

  i 
  

  

  