﻿CHAPTER 
  VIII. 
  

  

  LY— 
  ITS 
  EAYAGES, 
  H. 
  

   MEANS 
  OF 
  PREVENTING 
  ITS 
  INCREASE.^ 
  

  

  THE 
  HESSIAN 
  FLY— 
  ITS 
  RAVAGES, 
  HABITS, 
  AND 
  THE 
  

  

  INTRODUCTION. 
  

  

  Next 
  to 
  the 
  Rocky 
  Mountain 
  Locust, 
  the 
  Cotton 
  Worm, 
  and 
  Chinch 
  

   Bug, 
  the 
  Hessian 
  Fly 
  is 
  at 
  present 
  the 
  most 
  destructive 
  of 
  our 
  noxious 
  

   insects. 
  It 
  attacks 
  wheat, 
  our 
  most 
  important 
  agricultural 
  product, 
  and 
  

   at 
  times 
  has 
  been 
  so 
  abundant 
  as 
  to 
  cause 
  farmers 
  to 
  abandon 
  the 
  cult- 
  

   ure 
  of 
  this 
  grain 
  over 
  large 
  sections 
  of 
  the 
  Union. 
  While 
  the 
  fly 
  has 
  

   l)een 
  well 
  known 
  and 
  destructive 
  for 
  about 
  a 
  century, 
  the 
  vast 
  extension 
  

   within 
  a 
  decade 
  of 
  years 
  of 
  the 
  wheat-growing 
  area 
  of 
  the 
  West, 
  and 
  the 
  

   corresponding 
  prevalence 
  of 
  the 
  fly 
  in 
  the 
  Northern 
  Central 
  States, 
  to- 
  

   gether 
  with 
  its 
  wide-spread 
  destructiveness, 
  have 
  given 
  fresh 
  interest 
  

   and 
  importance 
  to 
  this 
  pest. 
  Moreover, 
  the 
  cultivation 
  of 
  wheat 
  in 
  the 
  

   New 
  England 
  States, 
  where 
  about 
  twenty 
  years 
  ago 
  it 
  was 
  abandoned 
  

   on 
  account 
  of 
  the 
  ravages 
  of 
  this 
  flj^ 
  and 
  the 
  Wheat 
  Midge, 
  has 
  been 
  re- 
  

   sumed 
  in 
  part, 
  so 
  that 
  the 
  dissemination 
  over 
  the 
  wheat 
  area 
  of 
  the 
  

   United 
  States 
  of 
  the 
  known 
  facts 
  in 
  regard 
  to 
  its 
  habits 
  and 
  mode 
  of 
  

   doing 
  injury 
  seems 
  necessary. 
  This 
  area, 
  as 
  seen 
  in 
  part 
  by 
  the 
  map^°^ 
  

   appended 
  to 
  this 
  chapter, 
  which 
  has 
  been 
  compiled 
  from 
  Walker's 
  Sta- 
  

   tistical 
  Atlas, 
  embraces 
  all 
  of 
  the 
  United 
  States 
  north 
  of 
  the 
  35th 
  par- 
  

   allel 
  of 
  latitude 
  and 
  east 
  of 
  the 
  93d 
  meridian, 
  with 
  the 
  addition 
  of 
  tracts 
  

   in 
  Dakota, 
  Montana, 
  Colorado, 
  New 
  Mexico, 
  and 
  Utah, 
  as 
  well 
  as 
  in 
  

   California, 
  Oregon, 
  and 
  Washington 
  Territory. 
  These 
  last-named 
  wheat 
  

   areas 
  were 
  not 
  mapped 
  by 
  General 
  Walker, 
  and 
  have 
  been 
  omitted 
  on 
  

   the 
  present 
  map, 
  since 
  the 
  Hessian 
  Fly 
  is 
  not 
  known 
  to 
  exist 
  west 
  of 
  

   eastern 
  Kansas. 
  

  

  Though 
  the 
  habits 
  of 
  the 
  Hessian 
  Fly 
  are 
  tolerably 
  well 
  known, 
  much 
  

   additional 
  knowledge 
  is 
  desirable 
  regarding 
  its 
  distribution, 
  its 
  breeding 
  

   habits, 
  and 
  its 
  parasites, 
  while, 
  in 
  order 
  to 
  properly 
  apply 
  the 
  best 
  pre- 
  

   ventive 
  remedies, 
  to 
  stamj) 
  out 
  the 
  pest 
  as 
  it 
  appears 
  iu 
  new 
  wheat 
  sec- 
  

   tions, 
  we 
  need 
  the 
  results 
  of 
  a 
  larger 
  number 
  of 
  experiments 
  as 
  to 
  the 
  

   effects 
  of 
  early 
  and 
  late 
  sowing, 
  what 
  varieties 
  of 
  wheat 
  to 
  sow, 
  and 
  as 
  

   to 
  the 
  value 
  of 
  manures 
  and 
  artificial 
  fertilizers 
  in 
  i^romoting 
  the 
  rapid 
  

   and 
  healthy 
  growth 
  of 
  the 
  young 
  wheat, 
  by 
  which 
  it 
  may 
  outgrow 
  the 
  

   weakening 
  effects 
  of 
  the 
  worm 
  and 
  ripen 
  its 
  graiii. 
  

  

  i^^Eeprinted, 
  Tvilh. 
  some 
  alterations 
  and 
  additions, 
  from 
  Bulletin 
  Ko. 
  4 
  of 
  the 
  U. 
  S. 
  Entomological 
  

   Commission. 
  

   I" 
  This 
  map 
  is 
  based 
  on 
  the 
  one 
  -which 
  appeared 
  in 
  Bulletin 
  No. 
  7, 
  out 
  with 
  corrections 
  and 
  additions. 
  

   198 
  

  

  