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JOURNAL  OF  HORTICULTURE  AND  COTTAGE  GARDENER. 
May  17,  1900. 
All  correspondence  relating  to  editorial  matters  should  be 
directed  to  “The  Editor,”  12,  Mitre  Court  Chambers, 
Fleet  Street,  Xondon,  E.c.  It  is  requested  that  no  one 
will  write  privately  to  any  of  our  correspondents,  seeking 
information  on  matters  discussed  in  this  Journal,  acs  doing  so 
subjects  them  to  unjustifiable  trouble  and  expense,  and  depart¬ 
mental  writers  are  not  expected  to  answer  any  letters  they 
may  receive  on  Gardening  and  Bee  subjects  through  the  post. 
If  information  be  desired  on  any  particular  subject  from  any 
particular  authority  who  may  be  named,  endeavour  will  be  made 
to  obtain  it  by  the  Editor.  Letters  of  inquiry  must  be  accom¬ 
panied  by  the  names  and  addresses  of  the  writers,  but  these  will 
neither  be  published  nor  disclosed  when  initials  or  noms  de  plume 
are  given  for  the  purpose  of  replies. 
■Correspondents  should  not  mix  up  on  the  same  sheet  questions  relating, 
to  Gardening  and  those  on  Bee  subjects,  and  it  is  convenient  when 
each  question  is  written  on  a  separate  sheet.  All  articles  intended 
for  Insertion  should  be  written  on  one  side  of  the  paper  only  ;  and 
the  name  and  address  of  each  writer  must  be  known  by  thi 
Editor,  though  not  necessarily  for  insertion.  We  cannot,  as  a 
rule,  reply  to  questions  through  the  post,  and  we  do  not  undei- 
take  to  return  communications  which,  for  any  reason,  cannot 
be  inserted. 
Vine  Leaves  (Inquirer). — We  could  not  find  any  of  the  insects 
referred  to  in  your  letter  on  the  under  side  of  the  Vine  leaves, 
they  being  so  fragile,  if  any  were  present  when  the  leaves  were  packed, 
as  to  have  completely  disappeared  in  transit.  With  the  exception  of 
some  slight  eating  of  the  leaves,  or  damage  to  the  tissue  by  a  bruise,  there 
was  nothing  the  matter  with  them,  they  being  quite  healthy  and  free 
from  pests.  On  the  Vines  there  were  examples  of  the  common 
“  spring! ails,”  which  are  usually  somewhat  abundant  where  there  is 
vegetable  or  animal  matter  in  a  state  of  decay,  and  even  in  damp 
earth.  They  are  sometimes  a  trouble  in  houses,  rasping  the  stems  of 
young  Cucumber  plants.  They  are  readily  destroyed  by  dusting  the 
soil  with  quicklime,  or  water  at  110°  to  120°  may  be  used,  a  light 
sprinkling  sufficing. 
Vine  Leaves  Eusted  (TV.  C.). — The  leaves  are  simply  rusted,  there 
being  no  evidence  of  malignant  vegetable  or  animal  organisms.  The 
rust  or  small  excrescences  on  the  under  side  of  the  leaves  have  been 
caused  by  keeping  the  house  somewhat  close,  and  then  admitting  air 
in  such  amount  as  to  suddenly  provoke  evaporation  from  the  foliage. 
The  parts  affected  perform  their  offices  very  imperfectly,  and  some¬ 
times  cause  the  leaves  to  assume  a  sickly  and  diseased  appearance,  and 
interfere,  though  not  generally  materially,  with  the  elaborating  and 
assimilating  functions.  There  is  also  some  scorching,  certainly  due  to 
neglect  of  ventilating  before  the  sun  had  acted  powerfully  upon  the 
house,  and  the  leaves  are  very  thin  in  tissue.  We  can  only  suggest 
earlier  and  more  judicious  ventilation,  the  night  temperature  being  kept 
at  60°  to  65°,  and  70°  to  75°  by  day,  increasing  to  80°,  85°  or  90°  with 
sun  heat,  air  being  admitted  between  70°  and  75°,  and  the  ventilation 
correspondingly  increased  with  the  advancing  temperature,  and  never 
given  so  as  to  lower  it. 
Melon  Plants  Collapsing  (T.  M.). — The  roots  of  the  specimen  appear 
quite  sound  and  free  from  pests,  but  at  the  collar  there  was  a 
slight  enlargement,  with  small  light  coloured  excrescences.  The  stem 
immediately  above  the  collar  was  somewhat  contracted,  and  on  this 
part  were  small  pustules.  We  have  long  been  acquainted  with  this 
affection,  which  is  akin  to  browning  or  “  brunure  ”  in  Vines.  The 
slight  enlargement  on  the  root  stem  just  within  the  soil  yielded  both  a 
specimen  of  root  stem  eelworm,  Tylenchus  obtusus,  and  the  mycelial 
hyphte  of  a  fungus,  possibly  that  of  the  Kidney  Bean  rust,  Glaeosporium 
Lindemuthianum,  the  small  pustules  on  the  stem  just  above  ground 
being  apparently  due  to  this  parasite,  though  no  fructifying  bodies  were 
observable.  Possiblv  the  fungus  passes  up  the  stem  as  plasma,  and  is 
thus  apt  to  be  confounded  with  the  browning  organism,  Pseudocommis 
Vitis  ;  but  whether  one  or  the  other,  or  both,  the  effect  is  to  stop  the 
ascent  of  the  sap  at  the  nodes  of  the  leaves,  which  collapse.  The 
disease  has  become  very  prevalent  of  late  years,  especially  in  Cucumbers 
grown  for  market,  the  conditions  of  culture  adopted  being  highly 
favourable  to  pests.  The  disease  receives  considerable  check  from 
dressings  of  a  mixture  of  air-slaked  lime  and  soot  in  equal  parts  by 
measure,  it  being  sprinkled  on  the  surface  of  the  soil  at  the  rate  of  a 
good  handful  to  the  square  yard,  repeating  occasionally.  Lime  applied 
to  the  soil  is  useful  as  a  preventive,  and  in  the  early  stages  of  attack 
Little’s  soluble  phenyle,  1  in  1000,  or  a  fluid  oz.  to  6|  gallons  of  water, 
has  given  good  results. 
Black  Spots  on  Clerodendron  Leaves  (Idem). — The  black  pustules 
on  the  under  side  of  the  leaves  are  those  of  some  unrecognised  species 
of  Phragmidium.  The  only  remedy  is  to  remove  and  destroy  the 
worst  infested  leaves  and  spray  the  whole  plant  with  methylated 
spirit  diluted  to  a  safe  strength,  which  must  be  ascertained  by  experi¬ 
ment.  Petroleum  emulsion  may  also  be  used  in  a  similar  manner,  or 
any  of  the  advertised  fungicides  in  accordance  with  the  instructions. 
Sweet  Peas  DefeCiive  (J.  O.  H.). — The  seeds  are  very  indifferent, 
only  the  larger  ones  being  perfect  ;  the  others,  more  than  half,  are  not 
only  very  small,  but  devoid,  in  the  specimens  examined,  of  embryos 
or  young  plants,  consequently  they  cannot  grow.  There,  however,  was 
no  trace  of  disease,  the  seeds  being  simply  imperfect,  possibly  due 
to  ineffective  fertilisation.  Only  the  good  seed  will  grow,  hence  the 
seeds  sown  will  not  come  up  properly  in  relation  to  the  number  placed 
in  the  soil.  The  seeds  do  not  appear  too  old  for  germination,  though 
that  is  a  matter  for  testing. 
Non-setting  of  Tomatoes  (J.  C.  A.).- — The  chief  cause  of  Tomatoes 
not  setting  their  fruit  is  excessive  vigour,  combined  with  a  too  close 
and  moist  atmosphere,  the  plants  not  having  enough  air,  and  possibly 
light.  Artificial  and  even  cross-fertilisation  may  be  useful  in  some 
cases,  also  rapping  the  footstalks  of  the  flowers  on  the  trusses  when  the 
blooms  are  fully  expanded  to  liberate  the  pollen,  but  unless  this  be 
perfect,  also  the  pistillate  organs,  there  can  be  no. good  result  ensue  by 
any  of  the  three  processes.  We  do  not  see  in  what  way  the  water 
could  affect  the  blossom  and  setting  of  the  fruit,  though  it  may  be 
largely  impregnated  with  or  contain  organic  matter,  which  would 
probably  be  corrected  by  adding  sulphate  of  lime  or  gypsum  to  it, 
about  an  ounce  per  gallon  counteracting  the  tendency  to  an  excess  of 
organic  acids  and  their  consequent  causticity.  Caustic  soda,  98  per 
cent,  purity,  may  be  procured  of  any  chemist  to  order,  there  not  being 
any  necessity  to  use  the  term  “  Greenbank  ”  in  this  country. 
Covering  Bank  at  Tennis  Lawn  (F.  B.). — The  position  and  height 
of  the  bank  is  such  that  there  are  few  suitable  plants.  Nothing  would 
answer  your  purpose  as  well  as  a  rather  rapid  growing  Stonecrop.  Of 
these  perhaps  the  best  would  be  Sedum  spurium  coccineum,  which 
would  form  a  dense  carpet  of  green,  with  crimson-purple  flowers  in 
June  and  July.  It  is  so  dense  that  the  balls  would  be  readily  seen. 
The  ordinary  variety  has  blooms,  too,  like  the  colour  of  the  balls.  Even 
brighter  would  be  Sedfim  reflexum,  with  showy  yellow  flowers.  These 
are,  however,  more  elevated  above  the  foliage,  and  might  hide  a  ball 
thrown  with  some  force.  Either  would  soon  cover  the  bank  if  planted 
a  few  inches  between  each  plant.  It  would  need  practically  no 
attention,  while  S.  reflexum  would  require  to  have  the  blooms  cut  off 
after  they  were  over.  Either  would  hold  up  the  soil  of  the  bank. 
8.  reflexum  would  look  better  in  or  out  of  bloom  than  S.  spurium 
coccineum,  but  the  latter  is  easier  to  keep  in  order.  Other  capital 
plants  are  unsuitable  on  account  of  their  hiding  the  balls.  Heli- 
anthemums  would  make  a  delightful  bank,  but  the  blooms  are  usually 
past  early  in  the  day.  Hypericum  calycinum  is  good,  but  would  hide 
the  balls. 
Pear  Tree  Leaves  Blistered  (P.  J.  P.). — The  leaves  are  infested  by 
the  Pear-leaf  mite,  Phytoptis  pyri,  which  causes  red  blister-like  spots 
to  appear  on  the  upper  surface  before  the  leaves  are  folly 
expanded,  and  later  on  they  change  to  yellowish  green,  then  to  a  dark 
brown  colour,  presenting  finally  a  dead,  dry,  brown  or  black,  corky 
appearance.  The  spots  occur  either  singly,  scattered  over  the  surface 
of  the  leaves,  or  coalesce,  forming  large  blotches  which  sometimes 
involve  a  considerable  portion  of  the  leaf.  The  mites  live  in  galls  set 
up  by  the  deposition  of  eggs  in  the  tissues  in  the  spring.  Spraying  or 
syringing  the  trees  wil.h  a  solution  of  petroleum  emulsion  has  a  good 
effect,  repeating  occasionally  from  early  spring  up  to  the  middle  of 
July,  the  mites  infesting  the  young  leaves  as  produced.  Any  badly 
infested  leaves  or  points  of  young  shoots  that  can  be  spared  may  be 
removed  and  burnt,  but  it  is  not  wise  to  defoliate  the  tree  or  trees  to 
an  excessive  extent.  The  spraying  or  syringing  should  be  practised 
about  every  fortnight  or  three  weeks,  with  2  ozs.  of  the  emulsion,  usually 
called  petroleum,  or  paraffin  softsoap,  to  a  gallon  of  water.  The  pest 
may  usually  be  prevented  by  a  single  spraying  of  the  trees  in  winter 
with  petroleum  emulsion  diluted  wiih  seven  parts  of  water,  it  being 
important  to  apply  the  solution  thoroughly  and  whilst  the  trees  are 
dormant. 
Beetles  in  a  'Vinery  (Idem). — The  insects  are  the  grooved  or  black 
Vine  weevil,  Otiorhynchus  sulcatus,  which  is  very  destructive,  both  as 
beetles  and  as  larvae  or  grubs.  The  beetles  feed  on  the  young  shoots 
of  Vines,  Peaches,  Apricots,  and  other  choice  fruit  trees;  and  are 
particularly  fond  of  the  young  fronds  of  Adiantums  and  many  other 
Perns.  The  larva?  are  usually  most  injurious  to  the  fleshy  or  young 
roots  of  Vines,  Raspberries  and  Strawberries,  and  frequently  do  great 
harm  to  potted  plants  in  greenhouses,  especially  to  Cyclamens,  as  well 
as  to  the  roots  of  a  great  variety  of  plants  in  gardens.  The  beetles 
feed  at  night,  when  they  should  be  sought  for  and  destroyed,  but  they 
fall  very  readily  off  their  food  plants  when  these  are  shaken,  or  when  a 
light  is  brought  into  their  vicinity  ;  hence  it  is  advisable  to  lay  cloths 
or  papers,  or  to  invert  an  open  umbrella  in  the  daytime  beneath,  and  at 
night  shake  the  plants  ;  then  collect  the  beetles  without  delay,  as  they 
sham  death  for  a  short-time  only,  and  place  in  a  vessel  containing  hot 
water  or  a  little  paraffin  oil.  This  practice  persisted  in  will  greatly 
reduce  their  number,  if  not  clear  them. ' 
