286 
JOURNAL  OF  HORTICULTURE  AND  COTTAGE  GARDENER. 
October  13,  1898. 
disease.  In  appearance  it  is  not  much  unlike  the  rust  which  appears 
on  the  backs  of  the  Oak  leaves  at  this  time  of  the  year,  but  I  suppose 
it  is  not  the  same  thing,  or  we  should  have  been  troubled  with  it  on 
Chrysanthemums  long  before  now. 
My  first  experience  with  the  infection  was  in  the  early  part  of 
this  year,  although  I  had  seen  a  large  collection  l  adly  smitten  with  it 
last  autumn.  I  found  it  on  some  cuttings  which  had  come  from  a 
friend  who  had  a  few  plants  attacked  with  it  in  the  autumn,  and  isolated 
them.  I  thought  I  would  try  what  a  mixture  of  petroleum  and  water 
would  do  for  the  pest,  and  accordingly  mixed  some  at  the  rate  of  a  wine- 
glassful  of  the  oil  to  a  gallon  of  water.  It  was  applied  to  the  affected 
plants  with  a  syringe,  and  I  am  glad  to  say  proved  very  effectual  in 
destroying  the  rust.  All  the  plants  have  been  standing  together 
during  the  summer,  and  I  did  not  see  any  more  of  the  rust  until  a 
few  weeks  ago,  when  it  made  its  appearance  on  several  plants.  I  at 
once  had  recourse  to  petroleum  and  water,  applying  with  the  syringe 
on  two  successive  evenings,  and  I  am  pleased  to  say  that  the  plan's  so 
treated  are  now  quite  clean,  save  the  circular  marks  where  the  spores 
burst  as  they  enlarged. 
My  object  in  penning  this  note  is  that  it  may  be  useful  to  some 
growers  who  are  troubled  with  leaf  rust,  and  want  a  simple  remedy 
without  delay,  as  it  is  evident  from  the  way  in  which  the  fungus 
spreads  that  it  requires  dealing  with  promptly.  I  lay  the  plants  on 
their  sides  when  syringing  them,  as  it  is  on  the  under  sides  of  the 
leaves  the  rust  appears  in  minute  spots  ;  but  as  the  flowers  are  now 
opening  sponging  will  have  to  be  resorted  to  instead  of  syringing,  to 
save  them  from  injury.  Warm  water  is  best  to  use,  as  the  petroleum 
mixes  with  it  much  better  than  with  cold. — Richard  Morse, 
Babbinyton  House  Gardens ,  Batli. 
Unfortunately  I  had  the  Chrysanthemum  rust  introduced  here 
in  the  spring,  on  plants  bought  from  a  well-known  nurseryman.  As 
I  have  been  successful  in  combating  it,  I  herewith  state  my  mode  of 
treatment,  as  it  may  be  of  service  to  other  growers. 
As  some  of  the  plants  were  badly  affected  on  their  arrival  I 
promptly  isolated  them  and  tried  different  remedies  on  various  plauts 
— viz.,  sulphide  of  potassium,  boiled  sulphur  and  lime,  and  a  weak 
mixture  of  paraffin,  but  the  only  one  which  proved  effectual  was  the 
Wye  Bordeaux  mixture,  as  published  in  “The  Chemistry  of  the 
Garden,”  by  Cousins.  This  compound  is  made  up  of — 
Copper  sulphate  (bluestone)  .  1  lb. 
Lime .  . .  . 1  ,, 
Agricultural  treacle  1  ,, 
Water  . 10  gals. 
I  found  the  treacle  in  this  formula  most  important,  as  it  made  the 
mixture  more  adhesive,  thus  giving  the  leaves  a  better  protective 
coatiDg.  The  plants  were  frequently  examined,  and  any  affected 
leaves  removed  and  burnt,  and  the  plants  sprayed  with  the  mixture. 
By  the  time  they  were  ready  for  their  flowering  pots  they  were 
perfectly  healthy  and  free  from  rust,  and  have  not  shown  the  slightest 
sign  of  it  since.  Perhaps  some  other  grower  who  has  been  troubled 
with  this  pest  and  has  succeeded  in  eradicating  it  will  state  his  mode 
of  treatment. — W.  Meredith,  Dudbroolce  Gardens,  Brentwood. 
THE  CONFERENCE  ON  THE  CHRYSANTHEMUM  RUST. 
That  the  Chrysanthemum  rust  is  attracting  a  great  amount  of 
attention  this  season  from  both  private  and  trade  growers  received 
additional  proof,  if  such  were  needed,  on  the  evening  of  Tuesday  last) 
the  11th  inst.,  when  a  large  and  deeply  interested  audience  assembled 
in  the  roomy  St.  Stephen’s  Hall  in  the  Royal  Aquarium,  Westminster, 
to  confer  upon  the  aspects  and  potentialities  of  this  comparatively  new 
but  dread  disease.  The  executive  of  the  National  Chrysanthemum 
Society,  under  whose  auspices  the  Conference  was  held,  had  arranged 
for  two  papers,  one  from  Mr.  P.  Waterer  of  The  Briars,  Fawkharn, 
upon  the  practical  aspects  of  the  rust,  and  the  other  dealing  with  the 
scientific  aspect  of  the  question,  from  Air.  Geo.  Massee,  the  celebrated 
mycologist  of  Kew. 
The  chair  was  taken  at  six  o’clock  by  Air.  T.  W.  Sanders,  the 
Chairman  of  the  Executive  Committee,  who,  in  opening  the  proceedings, 
said  that  he  thought  that  the  National  Chrysanthemum  Society  had 
done  excellent  work  in  calling  a  meeting  to  consider  this  very  im¬ 
portant  question,  which  vitally  affected  alike  trade  and  private  growers. 
As  the  hall  in  which  they  were  must  be  vacated  by  eight  o’clock,  he 
w’ould  call  at  once  upon 
Mr.  P.  Waterer  to  read  his  paper.  Air.  Waterer  opened  by 
thanking  the  Committee  of  the  N.C.S.  for  the  confidence  they  had 
reposed  in  him  in  committing  to  his  charge  the  treatment  of  the 
question  from  a  practical  point  of  view.  What  he  had  to  tell  them 
was  the  result  of  his  own  personal  experience,  but  he  would  ask  them 
to  bear  in  mind  that  such  experience  could  only  be  very  limited,  since- 
it  was  yet  only  a  short  time  ago  that  the  “  rust  ”  first  made  its 
appearance  upon  Chrysanthemums.  It  was  only  indeed  in  the  autumn 
of  last  year  that  attention  was  first  called  to  it,  and  little  had  been 
seen  or  heard  of  it  in  this  country  until  the  present  season.  The 
“rust”  was  not  to  be  confused  with  other  ailments  that  attacked  the 
Chrysanthemum.  Golden  Wedding  and  other  varieties  were  liable  ta 
a  peculiar  disease  which  discoloured  the  leaves  and  ultimately  caused 
collapse.  There  was  another  leaf  blight  that  affected  others,  and  this 
was  similar  to  that  to  be  seen  on  Plum  trees.  Aladame  Carnot  and  its 
sport  often  had  their  foliage  diseased  in  a  peculiar  kind  of  way,  whilst 
spotted  and  wrinkled  leaves  were  to  be  seen  on  very  many  varieties, 
although  this  was  brought  about  by  the  attacks  of  thrips  and  aphides. 
All  these  affections  were  quite  distinct  from  the  “rust ’’which 
they  had  met  to  consider.  This  “  rust  ”  appeared  as  brown  blotches, 
chiefly  on  the  lower  surface  of  the  leaves,  but  occasionally  on  the 
upper,  in  which  case  the  blotches  on  the  two  surfaces  corresponded. 
These  blotches  or  blisters  burst  in  about  a  week  after  they  first  made 
their  appearance,  and  disseminated  millions  of  spores,  which  in  the 
aggregate  appeared  like  snuff  upon  the  leaves.  Individually  the 
spores,  as  seen  under  the  microscope,  were  not  unlike  Carrot  seed.  The 
affected  leaves  turned  light  green  first  of  all,  then  brown,  and  finally 
perished.  He  found  on  his  plants  that  there  was  rarely  a  spot  below 
the  first  break,  but  passing  upwards  the  spotting  was  to  be  seen  as- 
high  as  the  bracts  that  surrounded  the  fiow'er  buds. 
Some  varieties  were  much  more  susceptible  to  the  disease  than 
others.  Thus  such  sorts  as  Airs.  G.  Carpenter,  Australian  Gold,  Sim¬ 
plicity,  and  Graphic  were  the  worst ;  whilst  Edith  Tabor,  Ella  Curtis, 
Matthew  Hodson,  and  C.  W.  Richardson  were  nearly  immune. 
The  worst  case  that  he  had  seen  was  from  Mr.  Needs  of  Woking, 
on  plants  that  had  been  raised  from  cuttings  struck  in  December, 
planted  out  in  April,  and  not  “  fed  ”  at  all.  It  was  found  that  if 
diseased  plants  were  cut  down  t1  e  young  shoots  thrown  up  from  tho 
bottom  were  free.  The  spores  of  the  rust  to  be  found  on  Pluma 
were  a  little  smaller,  but  otherwise  much  the  same,  and  he  had  found 
almost  identical  “  rust  ”  on  a  Dock,  and  on  other  wild  plants. 
It  had  been  stated  that  warm  wet  weather  was  favourable  to  the 
growth  of  the  fungi,  but  some  of  the  Plums  in  his  garden  were  badly 
affected,  and  yet  they  had  been  dry  as  could  be  for  weeks. 
He  had  tried  many  things  to  kill  the  spores,  including  dusting 
with  soot  and  tobacco  powder,  steeping  the  foliage  in  neat  paraffin  for 
nearly  a  week,  besides  spraying  with  mildew  specifics.  All  had  failed, 
however,  and  as  a  last  resource  he  had  induced  the  chemist  of  the 
Stock  Exchange  to  make  him  up  a  mixture  that  was  strong  enough 
to  kill  his  satanic  majesty  at  a  hundred  yards,  and  even  it  had  failed. 
The  only  suggestion  that  he  could  make,  therefore,  was. to  give  the 
rubbish  heap  a  wide  berth,  for  he  thought  the  spores  were  introduced 
into  the  potting  soil  in  this  way,  and  to  syringe  with  preventives. 
Mr.  G.  Massee  was  next  called  upon  to  favour  the  company  with 
the  scientific  aspects  of  the  case.  In  his  usual  happy  way,  and  with 
his  customary  aptness  of  simile  and  lucidity  of  description,  Air.  Alassee 
held  his  audience  in  rapt  attention  whilst  he  gave  them  the  views  of 
the  scientist  upon  the  matter.  The  fungus,  he  said,  had  been  abused 
all  round,  and  he  felt  inclined  to  take  out  a  brief  for  it,  for  it  had  been 
perfectly  just  in  doing  what  it  had  done,  and,  under  the  circumstances, 
it  could  not  well  have  done  less.  It  was  the  Chrysanthemum  grower’a 
own  fault  that  the  rust  was  in  existence  to-day.  The  keynote  of  the 
whole  thing  was  “  overcrowding.”  Of  course  he  was  aware  that  the 
trade  grower  would  say  that  if  Chrysanthemum  growing  was  to  be 
made  to  pay,  he  must  keep  his  plants  close  together.  It  was  difficult 
for  him  to  answer  this  to  their  satisfaction,  but  he  could  only  ask  if  it 
was  not  better  to  have  one  healthy  plant  than  fifty  unhealthy  ones  ?' 
The  rust  could  not  have  come  into  existence  as  a  Chrysanthemum  pest 
if  this  overcrowding  had  not  been  practised. 
Another  point  was  that  they  had  progressed  in  every  branch  of 
horticulture  except  one — they  had  forgotten  to  study  the  peculiarities 
of  the  life  history  of  parasitic  fungi,  although  it  was  done  in  every 
civilised  country  save  Britain.  He  did  not  mean  that  every  gardener 
should  exhaustively  take  up  the  study  of  mycology,  for  there  were, 
perhaps,  too  many  mycologists  already  ;  it  was  only  necessary  to 
understand  the  important  points  in  the  life  history  of  the  fungi.  This 
neglect,  with  the  tendency  to  overcrowd,  was  entirely  to  blame.  Our 
cultivators  nowadays  crowded  their  plants  together  in  an  extremely 
small  area.  If  the  crowding  turned  out  well,  all  well  and  good ;  if  not, 
then  they  blamed  the  rust.  Pieces  of  many  diseased  plants  had  been 
