44 
JOURNAL  OF  HORTICULTURE  AND  COTTAGE  GARDENER. 
July  10,  1902. 
***  All  correspondence  relating  to  editorial  matters  should  be  directed 
to  “  The  Editor,”  12,  Mitre  Court  Chambers,  Fleet  Street, 
London,  E.C.  It  is  requested  that  no  one  will  write  privately 
to  any  of  our  correspondents,  seeking  information  on  matters 
discussed  in  this  J ournal,  as  doing  so  subjects  them  to  unjustifiable 
trouble  and  expense. 
Plan  of  a  Bothy— Competition. 
In  answer  to  a  query  from  “A.  B.,”  and  in  order  to  keep  this 
before  the  minds  of  readers,  we  print  below  the  rules  for  the 
Journal  Bothy  Plan  Competition.  It  will  be  remembered  that 
“Well-wisher”  promises  a  first  prize  of  £3,  and  the  Editor  sup¬ 
plies  a  second  prize  of  £1. 
The  rules  of  the  competition  are  as  follows  : — The  plati,  drawn 
to  scale,  must  not  exceed  7in  broad  by  Tin  deep,  and  must  be 
clearly  defined  on  stout  paper.  The  plan  must  provide  suitable 
accommodation  for  six  men,  and  the  cost  of  the  building  ought  not 
to  exceed  £200  to  £220.  A  statement  of  the  general  items  of 
cost  should  accompany  the  plans,  together  with  any  written 
comments  thereon.  The  competition  is  open  until  Christmas, 
1902,  by  which  date  all  plans  must  be  in  the  hands  of  the  Editor. 
The  sender’s  name  and  full  address  should  be  enclosed  when  send¬ 
ing  the  plan,  and  the  sender  will  alone  be  held  responsible  for  it. 
DO!  BLE  IRIS  (F.  A.). — Purely  a  case  of  excessive  vigour, 
and  synchronous  with  fasciation  in  the  Liliums.  We  have 
doubts  as  to  whether  it  is  “  fixed,”  and  at  any  rate  it  is  ugly. 
Try  the  effects  of  planting  and  growing  it  in  poor  soil. 
MULBERRY  SHOOT  BEARING  CATKINS  (D.  W.).— 1 The 
circumstancesi  of  the  “  falling-away  of  the  male  catkins  ”  may 
have  led  our  correspondent  into  error,  for  certainly  the  common 
Mulberry  is  monoecious  as  the  shoots  you  send  so  well  show,  and 
our  passing  the  statement  was  an  unfortunate  oversight.  Of 
course  the  staminate  flowers  are  purposeless  after  the  pollination 
has  occurred,  whereas  the  female  flowers  give  rise  to  fruit. 
ARTIFICIAL  MANURE  FOR  VINES  (J.  Q.).— In  our  issue 
of  July  3  your  queries  were  replied  to,  your  letter  having  gone 
astray  in  consequence  of  its  being  addressed  “  The  Editor  ”  only 
instead  of  ‘  The  Editor  of  the  Journal  of  Horticulture,”  other 
publications  being  issued  from  12,  Mitre  Court  Chambers.  Clay’s 
fertiliser,  about  which  you  inquire,  is  a  good  all-round  artificial 
manure,  and  would  help  the  Vines  to  finish  their  crops  as  well  as 
assist  them  to  store  matter  for  the  succeeding  cne.  The  query 
about  weed-killer  was  also  answered  July  3,  to  “  Idem,”  page  20. 
The  weed-killers  you  mention  are  effective  for  their  purpose,  but 
we  cannot  undertake,  for  obvious  reasons,  to  refer  to  any 
proprietary  article  in  particular,  unless  under  special  circum¬ 
stances. 
GROWING  DAHLIAS  FOR  EXHIBITION  (Young  Beginner). 
— Both  Fancy  and  Show  Dahlias  require  a.  rich,  moderately  heavy 
soil  to  give  the  best  results,  and  should  be  stirred  deeply  and 
liberally  manured.  It  is  not,  however,  advisable  to  apply  strong 
manure  in  spring,  or  over-luxuriance  in  foliage  would  thereby  be 
encouraged  at  the  expense  of  the  production  of  flowers.  A  light, 
open  situation,  free  from  the  shade  of  trees,  is  best,  but  surround¬ 
ing  shrubs  or  dwarf  trees  are  often  an  advantage  to  Dahlias  by 
protecting  them  from  high  winds.  Planting  should  not  be 
attempted  before  the  beginning  of  June  in  most  localities,  and 
the  plants  should  be  stout,  clean,  and  healthy,  with  one  stem. 
A  distance  of  6ft  should  be  allowed  from  plant- to  plant;  water 
after  planting,  and  apply  a  temporary  stake  to  each  for  a  time ; 
afterwards  place  a  stout  stake  to  each  plant  and  secure  the  main 
stem  to  it.  When  the  heads  commence  forming  reduce  the 
growths  to  about  four  of  the  most  promising,  and  securely  affix 
these  to  the  main  stake  by  tying,  or  preferably  secure-  each  to  a 
stake  separately,  for  bundling  will  not  do,  as  the  foliage  must 
have  full  exposure-  to  light.  On  the  shoots  thus  obtained  there 
will  appear  flowers  in  due  course.  These  must  be  thinned  while 
quite  young,  leaving  the  central  one  on  each  shoot  and  removing 
the  side  buds.  When  these  reserved  buds  are  beginning  to  develop 
into  flower  they  must  be  shaded  from  sun,  and  protected  from 
rain,  and  in  due  course  you  will  have  good  or  bad  blooms,  accord¬ 
ing  to  the  management.  This  we  cannot  describe — it  is  an  art 
that  must  be  learned,  but  we  may  say  that  Dahlias  are  much 
benefited  by  frequent  applications  of  water  during  the  summer, 
ar^d  by  liquid  manure  after  the  buds  are  formed,  the  ground  being 
kept  mulched  with  short  manure.  The  plants  must  be  kept 
free  from  insect  pests,  especially  earwigs,  or  they  will  spoil  the 
foliage  and  also  the  blooms. 
PELARGONIUM  SPORT  (C.  S.).— We  do  not  understand 
your  letter.  Is  it  that  you  do  not  know  which  is  the  variety 
Princess  Alexandra  and  which  the  sport?  We  do  not  know  the 
variety,  as  Pelargoniums  are  florists’  flowers,  which  we  do  not 
attempt  to  keep  up  with.  Send  to  Messrs.  Cannell  and  Sons, 
Swanley.  The  flowers  fall  easily  to  pieces. 
GRUB-EATEN  FRUITS  OF  MARIE  LOUISE  PEAR  (North 
Riding). — The  Pears  are  infested  by  the  larvae  or  maggots  of  the 
Pear-gall  gnat  or  Pear  midge,  Diplo-sis  pyrivora,  a  small  two¬ 
winged  fly,  which  appears  early  in  spring,  commonly  before  the 
flowers  of  the-  Pear  trees  open,  and  remains  about  ten  days.  After 
pairing  the  female  deposits  her  eggs  inside  the  blossom  envelope, 
when  the  Pear  flower  has  opened  sufficiently  for  the  insertion  of 
her  long  ovipositor.  The  eggs  are  placed  at  the  base  of  the 
blossom  and  sometimes  in  the  neck  of  the  ovary,  and  in  three  or 
four  days  the  eggs  hatch  into  tiny  maggots  in  the  ovary  of  the 
embryo  fruit,  where  they  feed  upon  the  growing  tissues,  and  in 
consequence-  give  rise  to  a  gall.  The  effect  is  to  destroy  the  core 
and  ovules,  and  the  maggots  continue  until  full-fed,  which  occurs 
early  in  June  in  forward  seasons,  when  decay  follows,  and  the 
fruit  either  falls  or  cracks,  and  the  maggots  emerge,  dropping  to 
the  ground.  The  maggots  enter  the  soil  an  inch  or  two,  and  after 
resting  awhile,  make  oval  cocoons  of  silken  threads,  mixed  with 
particles  of  earth.  In  these  cocoons  they  remain  apparently 
unchanged  until  the  following 'spring,  then  change  to  pupae,  and 
after  a  month  in  that  state  the  flies  emerge,  always  by  the  time 
the  Pear  blossoms  are  in  good  colour,  and  have  nothing  to  do  but 
await  the  expansion  of  the  petals  for  inserting  the  eggs.  These 
are  seldom  less  than  a  dozen,  and  often  many  more  in  number, 
which  means  a  corresponding  number  of  maggots,  so  that  there 
is  no  wonder  they  make  such  speedy  work  of  the  Pear.  The  pre¬ 
ventive  measures  recommended  are : — 1.  Catching  the  flies  on 
strips  of  tin  about  1ft  long  and  3in  wide,  smeared  on  both  sides 
with  a  substance  formed  of  one  part  sweet  oil  and  two  parts 
resin  melted  together,  affixing  the  traps  in  the  forks  of  the 
trees,  or  so  that  they  will  be  level  with  or  just  above  or  outside 
the  blossoms.  The  traps  must  be  in  position  just  before  the 
flowers  unfold,  continuing  for  a  fortnight.  2.  Spray  the  trees 
with  some-  “  fine  ”  smelling  substance,  such  as  tar  water,  fib  of 
gas  tar  being  boiled  for  half  an  hour,  or  until  it  will  readily  mix 
with  water,  in  two  gallons  of  water,  and  then  dilute  to  50  gallons 
with  water,  applying  just  before  the  flowers  open.  3.  While  the 
maggots  are  in  the  fruit,  the  removal  of  the  affected  Pears  and 
burning  them  never  fails.  4.  When  the  larvse  have  left  the  fruit, 
which  takes  place  about  the  middle  of  June,  later  in  backward 
seasons  and  in  the  open,  but  earlier  against  walls,  supply  a  dress¬ 
ing  of  kainit,  lOcwt.  per  acre,  71b  per  rod,  or  4oz  (rather  less)  per 
square  yard  just  after  rain.  The  salt  will  be  dissolved  by  the 
soil  moisture,  and  the  solution  coming  into  contact  with  larvae 
destroys  them.  In  the  case  of  cultivated  land  the  kainit  may  be 
lightly  pointed  in.  The  most  hateful  thing  to  pests  is  good  cul¬ 
tural  methods  that  make  for  their  disturbance  and  eradication. 
But  when  the  garden  or  orchard  so  treated  adjoins  another  garden 
or  orchard  that  knows  neither  soil  cultivation  nor  essential  top 
management,  all  the  labour  will  be  in  vain,  as  the  Pear-gall  gnats 
are  bound  to-  find  their  way  from  the  neglected  to  the  cultivated 
trees.  In  the  Journal  of  Horticulture ,  June  3,  1897,  page  486,  is 
an  article  by  Mr.  G.  Abbey  on  this  pest,  and  on  page  487  of  the 
same  number  are  illustrations  showing  the  life  history  of  the  Pear- 
gall  midge. 
