﻿The 
  following 
  classification 
  of 
  insect 
  injuries 
  to 
  the 
  beet 
  and 
  

   arrangement 
  of 
  injurious 
  insects 
  under 
  them 
  in 
  economic 
  groups 
  is 
  

   intended 
  as 
  an 
  aid 
  to 
  these 
  identifications. 
  

  

  KEY 
  FOR 
  THE 
  RECOGNITION 
  OF 
  INSECT 
  INJURIES 
  TO 
  BEETS, 
  

  

  Plant 
  apparently 
  injured, 
  but 
  its 
  substance 
  above 
  ground 
  not 
  evidently 
  

  

  eaten 
  in 
  a 
  way 
  to 
  account 
  for 
  the 
  injury. 
  . 
  . 
  . 
  .2. 
  

  

  I 
  Substance 
  of 
  leaf 
  evidently 
  more 
  or 
  less 
  eaten 
  away. 
  (Injuries 
  by 
  biting 
  

   [ 
  insects; 
  arrested 
  by 
  arsenical 
  poisons.) 
  . 
  . 
  . 
  .7. 
  

  

  Leaves 
  discolored 
  — 
  that 
  is, 
  specked, 
  spotted, 
  or 
  blotched 
  with 
  whitish, 
  

   yellowish, 
  or 
  purple; 
  often 
  more 
  or 
  less 
  wrinkled 
  or 
  curled. 
  (Injuries 
  

  

  2 
  •{ 
  by 
  sucking 
  insects 
  or 
  by 
  mites; 
  arrested 
  by 
  kerosene 
  sprays.) 
  3. 
  

   I 
  Leaves 
  not 
  specked, 
  spotted, 
  wrinkled, 
  or 
  blistered 
  to 
  account 
  for 
  injury; 
  

   [ 
  under-ground 
  part 
  of 
  plant 
  affected. 
  . 
  . 
  . 
  .6. 
  

  

  Under 
  surface, 
  when 
  very 
  closely 
  examined, 
  seen 
  to 
  be 
  covered 
  with 
  a 
  very 
  

   fine 
  loose 
  dirty 
  web. 
  Discolored 
  blotches 
  large, 
  more 
  or 
  less 
  cupped 
  

  

  3 
  ■{ 
  beneath. 
  Minute 
  oval 
  reddish 
  specks 
  moving 
  on 
  surface 
  of 
  leaf. 
  

  

  J?ed 
  Spiders, 
  p. 
  58. 
  

  

  Surface 
  of 
  leaf 
  not 
  webbed. 
  . 
  . 
  . 
  . 
  . 
  .4. 
  

  

  I 
  Small 
  blister-like 
  cavities 
  in 
  the 
  thickness 
  of 
  the 
  leaf, 
  making 
  colorless 
  

   < 
  translucent 
  spots. 
  . 
  . 
  , 
  Leaf- 
  miners, 
  p. 
  59. 
  

  

  ( 
  Leaf 
  without 
  blister-like 
  spots. 
  . 
  , 
  . 
  . 
  . 
  • 
  5- 
  

  

  f 
  Many 
  small 
  greenish, 
  yellowish, 
  or 
  grayish 
  soft-bodied 
  hopping 
  insects 
  on 
  

   I 
  leaves. 
  Empty 
  skins 
  of 
  the 
  same 
  usually 
  scattered 
  on 
  the 
  surface. 
  

  

  <j 
  Discolored 
  specks 
  of 
  the 
  leaf 
  small. 
  . 
  Leaf-hopf<crs, 
  p. 
  62. 
  

  

  I 
  Leaf-hoppers 
  not 
  abundant. 
  Discolorations 
  usually 
  larger. 
  

   [ 
  rianl-lice, 
  leaf-bugs, 
  flant-hugs, 
  and 
  other 
  Ilemiptera, 
  pp. 
  80-100. 
  

  

  I 
  Small 
  sluggish 
  greenish 
  insects 
  numerous 
  on 
  underground 
  growth, 
  usually 
  

  

  I 
  associated 
  with 
  ants. 
  . 
  . 
  , 
  Root-lice, 
  p. 
  159. 
  

  

  I 
  Roots 
  eaten, 
  excavated, 
  or 
  burrowed. 
  

  

  [ 
  IViretvorms, 
  zvhite 
  grubs, 
  muck-beetles,* 
  •^^. 
  161-165. 
  

  

  3 
  Leaves 
  cut 
  off 
  at 
  ground. 
  .... 
  Cutiuorms, 
  p. 
  100. 
  

  

  ( 
  Leaves 
  not 
  cut 
  off. 
  ....... 
  8. 
  

  

  j 
  Leaves 
  rolled 
  or 
  folded. 
  ...... 
  9. 
  

  

  ( 
  Leaves 
  not 
  merely 
  rolled 
  or 
  folded. 
  . 
  . 
  . 
  . 
  .10. 
  

  

  I 
  Leaf 
  rolled 
  at 
  edge, 
  small 
  striped 
  green 
  caterpillar 
  within 
  the 
  roll. 
  

   ; 
  Leaf-rollers, 
  p. 
  105. 
  

  

  I 
  Leaf 
  folded 
  lengthwise 
  at 
  middle, 
  sides 
  closely 
  webbed 
  together, 
  small 
  

   [ 
  green 
  caterpillar 
  usually 
  in 
  fold 
  beneath 
  web. 
  Leaf-folders, 
  p. 
  106. 
  

  

  ( 
  Plant 
  more 
  or 
  less 
  covered 
  or 
  inclosed 
  with 
  loose 
  open 
  web, 
  leaves 
  eaten 
  

   by 
  spotted 
  or 
  striped 
  caterpillars. 
  . 
  . 
  U'eb-icorms, 
  p. 
  106. 
  

  

  ' 
  Plant 
  not 
  webbed, 
  leaves 
  free. 
  ..... 
  11. 
  

  

  I 
  Leaves 
  riddled 
  by 
  small, 
  usually 
  circular 
  holes. 
  Many 
  small 
  hard 
  leaf- 
  

  

  J 
  beetles 
  present. 
  . 
  ■ 
  Plant-beetles, 
  )lea-beetles, 
  etc., 
  pp. 
  112-12S. 
  

  

  I 
  Leaves 
  ragged 
  by 
  coarse 
  irregular 
  openings 
  or 
  eaten 
  away 
  irregularly 
  from 
  

   [ 
  edges. 
  . 
  Grasshofpers, 
  beetles, 
  caterpillars, 
  etc., 
  pp. 
  128-158. 
  

  

  ♦See 
  also 
  the 
  dark-sided 
  cutworm 
  (Curneadcs 
  inessoriu), 
  p. 
  102, 
  foot-note. 
  

  

  