﻿10 
  DECIDUOUS 
  FRUIT 
  INSECTS 
  AND 
  INSECTICIDES. 
  

  

  weeks 
  in 
  July. 
  At 
  this 
  time 
  also 
  larvae 
  of 
  the 
  grapeberry 
  moth 
  are 
  

   hatching 
  from 
  eggs 
  deposited 
  upon 
  the 
  grape 
  berries. 
  Since 
  it 
  is 
  

   impossible 
  to 
  cover 
  thoroughly 
  the 
  underside 
  of 
  the 
  grape 
  leaves 
  in 
  

   spraying 
  for 
  the 
  grape 
  leafhopper 
  without 
  thoroughly 
  wetting 
  the 
  

   grape 
  clusters 
  it 
  is 
  reasonable 
  to 
  infer 
  that 
  the 
  addition 
  of 
  arsenate 
  

   of 
  lead 
  would 
  also 
  assist 
  in 
  checking 
  the 
  injury 
  to 
  the 
  grape 
  berries 
  

   by 
  the 
  larva? 
  of 
  the 
  grape 
  berry 
  moth. 
  In 
  addition 
  to 
  this 
  the 
  Bor- 
  

   deaux 
  mixture 
  will 
  control 
  the 
  development 
  of 
  mildew 
  on 
  the 
  stems 
  

   of 
  the 
  grape 
  clusters. 
  The 
  upper 
  surface 
  of 
  the 
  grape 
  leaves 
  also 
  is 
  

   covered 
  during 
  this 
  process 
  (see 
  PL 
  III, 
  fig. 
  2) 
  ; 
  hence, 
  if 
  arsenate 
  of 
  

   lead 
  is 
  present 
  with 
  the 
  tobacco 
  extract 
  this 
  application 
  will 
  control 
  

   the 
  late 
  emerging 
  beetles 
  of 
  the 
  grape 
  rootworm. 
  As 
  intimated 
  

   above, 
  the 
  advisability 
  of 
  making 
  this 
  combination 
  of 
  ingredients 
  

   must 
  be 
  decided 
  by 
  the 
  prevalence 
  and 
  abundance 
  in 
  the 
  vineyard 
  

   to 
  be 
  treated 
  of 
  the 
  several 
  insects 
  referred 
  to. 
  It 
  should 
  also 
  be 
  

   borne 
  in 
  mind 
  that 
  this 
  combination 
  treatment 
  is 
  submitted 
  as 
  a 
  

   suggestion. 
  

  

  The 
  mixing 
  of 
  the 
  tobacco 
  extracts 
  with 
  Bordeaux 
  and 
  arsenate 
  of 
  

   lead 
  this 
  season 
  was 
  done 
  for 
  the 
  sole 
  purpose 
  of 
  determining 
  if 
  this 
  

   mixture 
  would 
  be 
  injurious 
  to 
  the 
  grape 
  foliage 
  and 
  berries. 
  As 
  men- 
  

   tioned 
  above, 
  no 
  injurious 
  effect 
  to 
  the 
  vine 
  was 
  observed. 
  Arsenate 
  

   of 
  lead 
  is 
  the 
  only 
  arsenical 
  that 
  should 
  be 
  used 
  with 
  tobacco 
  extracts, 
  

   since 
  both 
  arsenite 
  of 
  lime 
  and 
  Paris 
  green 
  cause 
  serious 
  burning 
  of 
  

   the 
  foliage 
  when 
  mixed 
  with 
  the 
  tobacco 
  extracts. 
  

  

  EFFECT 
  OF 
  GRAPE 
  LEAFHOPPER 
  CONTROL 
  ON 
  QUALITY 
  OF 
  FRUIT 
  

  

  As 
  mentioned 
  in 
  foregoing 
  paragraphs 
  dealing 
  with 
  results 
  secured 
  

   in 
  these 
  spraying 
  experiments 
  with 
  tobacco 
  extracts, 
  it 
  was 
  observed 
  

   that 
  in 
  every 
  case 
  where 
  the 
  nymphs 
  were 
  successfully 
  controlled 
  the 
  

   berries 
  of 
  the 
  grape 
  clusters 
  from 
  these 
  vines 
  were 
  much 
  larger, 
  a 
  

   darker 
  purple 
  in 
  color, 
  and 
  much 
  sweeter 
  than 
  the 
  fruit 
  from 
  un- 
  

   sprayed 
  vines 
  in 
  the 
  same 
  vineyard. 
  In 
  order 
  to 
  ascertain 
  if 
  there 
  

   was 
  any 
  marked 
  difference 
  in 
  the 
  sugar 
  content 
  of 
  the 
  grapes 
  from 
  

   vines 
  growing 
  in 
  the 
  sprayed 
  and 
  unsprayed 
  plats 
  samples 
  represent- 
  

   ing 
  the 
  average 
  condition 
  of 
  the 
  fruit 
  from 
  sprayed 
  and 
  unsprayed 
  

   vines 
  from 
  experimental 
  plats 
  in 
  the 
  vineyards 
  of 
  Mr. 
  J. 
  E. 
  Beatty 
  

   and 
  Mr. 
  W. 
  E. 
  Gray, 
  North 
  East, 
  Pa., 
  were 
  submitted 
  for 
  analysis. 
  

  

  These 
  samples 
  of 
  grapes 
  taken 
  for 
  analysis 
  were 
  forwarded 
  to 
  Prof. 
  

   Wm. 
  B. 
  Alwood, 
  in 
  charge 
  of 
  Enological 
  Investigations 
  at 
  the 
  labora- 
  

   tory 
  of 
  the 
  Bureau 
  of 
  Chemistry 
  located 
  at 
  Sandusky, 
  Ohio. 
  The 
  

   samples 
  were 
  there 
  analyzed 
  in 
  connection 
  with 
  the 
  extended 
  studies 
  

   that 
  Prof. 
  Alwood 
  is 
  making 
  of 
  the 
  chemistry 
  of 
  many 
  varieties 
  

   of 
  grapes 
  grown 
  in 
  the 
  eastern 
  United 
  States 
  in 
  relation 
  to 
  wine 
  

   production. 
  

  

  The 
  report 
  received 
  from 
  Prof. 
  Alwood 
  on 
  these 
  samples 
  of 
  grapes 
  

   from 
  these 
  sprayed 
  and 
  unsprayed 
  experimental 
  plats 
  is 
  given 
  in 
  

   Table 
  I. 
  

  

  