140 
JOURNAL  OF  HORTICULTURE  AND  COTTAGE  GARDENER. 
August  8,  1901. 
supplying  sufficient  water  to  keep  the  foliage  in  good  condition,  and 
securing  air  moisture  by  damping  the  floor  and  borders  in  the  morning 
andjafternoon,  as  an  arid  atmosphere  favours  thrips  and  red  spider,  and 
the  premature  ripening  of  the  foliage  ;  dryness  at  the  roots  also  favours 
these  pests,  tends  to  the  fruit  ripening  unduly,  and  may  render  it 
mealy.  A  slight  shade  is  sometimes  beneficial  when  the  sun  is 
powerful,  and  the  apex  of  the  fruit  fully  exposed  to  its  rays  beneath 
large  panes  of  glass,  to  prevent  the  fruit  ripening  too  quickly  and 
becoming  discoloured  at  the  apex,  or  when  it  ripens  in  exoess  of  the 
demands.  Ants  are  sometimes  very  troublesome  on  suoh  fruits, 
especially  Nectarines,  eating  into  the  choicest  at  the  apex.  Poisons 
are  not  safe  to  use  at  such  times.  The  most  suitable  means  of  riddance 
is  to  place  some  partially  picked  bones,  such  as  come  from  table,  in 
their  haunts,  and  when  they  are  feeding  on  the  meat  place  them  in 
boiling  water.  The  bait  should  be  dried  before  using  again,  and  this 
persisted  in  will  clear  a  house  of  the  ants. 
Late  Houses. — The  wood  should  be  laid  in  thinner  than  is  customary 
with  trees  in  earlier  houses,  so  as  to  give  it  a  better  chance  to  ripen, 
and  the  foliage  advantage  to  assimilate  food,  and  store  it  up  in  the 
wood,  whilst  the  buds  are  perfectly  formed.  Attend,  therefore,  to 
thinning  and  regulating  the  growths.  Gross  shoots  tend  to  impoverish 
the  weaker,  appropriate  an  undue  amount  of  sap,  prevent  an  equal 
distribution  of  the  nourishment,  and  are  seldom  fruitful ;  they  mostly 
fall  a  prey  to  gum  disease,  and  are  best  removed  in  favour  of  less 
exuberant  growths, 
striving  to  secure 
an  even  spread  of 
moderately  strong 
short -jointed  wood. 
Ventilate  freely  in 
the  early  part  of 
the  day,  allow  a 
good  heat  from  sun 
through  the  day, 
and  close  in  good 
time,  so  as  to  run 
up  to  85°.  This  will 
only  be  necessary 
where  the  fruit  is 
required  accele¬ 
rated  in  ripeniDg. 
Sun  heat  will  not 
do  any  harm  after 
evaporation  has 
been  going  on  for 
some  time,  but  it  is 
desirable  to  admit 
a  little  air  before 
nightfall  to  allow 
the  pent-up  mois¬ 
ture  to  escape,  and 
the  gradual  cooling 
of  the  house  will 
induce  rest.  Early 
ventilation  is 
necessary  for  the 
solidification  of  the  growth.  Forcible  syringings  will  keep  the  trees 
free  from  red  spider,  and  should  be  continued  until  the  fruit 
commences  to  ripen.  Keep  the  borders  well  supplied  with  water  or 
liquid  manure. — St.  Albans. 
TO  CORRESPONDENTS 
•  • 
Peach  blister,  with  accompanying  fungus  Ascomycees  deformans. 
Next  Week’s  Events, 
Saturday,  August  10th.  —  Nelson  and  District  Horticultural  and 
Industrial  Art  Society’s  Annual  Show;  Keighley  Horticultural 
Society. 
Tuesday,  August  13th. — R.H.S.  Committees. 
Wednesday,  August  14th. — Clevedon  Exhibition;  Sevenoaks  Exhibition. 
Phenological  Observations. 
August  9th  to  August  15th. 
9  Fri.  Linnet’s  song  ceases. 
10  Sat.  Silver-spotted  skipper  butterfly  seen. 
11  Sun.  Dog  days  end. 
12  Mon.  Swallows  and  martens  congregate. 
13  Tu.  Marten’s  second  brood  fledged. 
14  Wed.  Goldfinch’s  song  ceases. 
15  Thr.  Staphyline  seen. 
Plants  dedicated  to  each  day. 
Common  Ragwort. 
Common  Balsam. 
China  Aster. 
Tall  Marsh  Sowthistle. 
Marsh  Groundsel. 
Zinnia. 
Virgin’s  Bower. 
Trade  Catalogue  Reseif«d. 
Little  &  Ballantvne,  Carlisle. — Bulb  Cata’ogue. 
All  correspondence  relating  to  editorial  matters  should  be  directed 
to  “The  Editor,”  12,  mitre  Court  chamber!,  Fleet  Street, 
Xiondon,  E.c.  It  is  requested  that  no  one  will  write  privately 
to  any  of  our  correspondents,  seeking  information  on  matters 
discussed  in  this  Journal,  as  doing  so  subjects  them  to  unjustifiable 
trouble  and  expense. 
Cucumbers  Diseased  (R.  M.). — The  soil  is  too  rich  and  too  moist; 
the  atmospherio  temperature  is  too  low. 
Peach  Blister  ( Amateur ). — Can  you  tell  me  what  is  the  matter  with 
my  Peach  trees  ?  All  the  leaves  are  like  those  I  send.  I  am  anxious 
to  know  the  cause  of  the  evil,  and  the  remedy.  [The  samples  sent 
to  us  are  blistered.  An  engraving  of  blistered  leaves,  prepared  after  a 
microscopical  examination,  is  given  herewith.  In  the  cut,  A  shows  the 
Peach  blister  as 
commonly  seen ; 
when  the  fungus 
is  present  a  white 
bloom  may  here 
and  there  be  de¬ 
tected  on  the  red 
blister,  and  this 
bloom  when  mag¬ 
nified  one  thousand 
diameters  linear  is 
seen  as  shown  at  B. 
It  is  excessively 
minute  as  com¬ 
pared  with  the 
thickness  of  the 
leaf  and  its  com¬ 
ponent  cells ;  the 
latter  magnified  to 
the  same  scale  are 
seen  at  c.  The 
fungus  consists  of 
a  stratum  of  tine 
threads,  which 
throw  up  a  series 
of  small  flask-like 
bodies  (asci)  filled 
with  spores,  the 
flasks  being  mixed 
with  necklace-like 
growths  D,  which 
are  clearly  a 
second  form  of  fruit.  Each  ascus,  or  flask,  contains  eight  spores,  which 
at  certain  moments  open  at  the  top,  as  at  e,  and  discharge  their  spores 
(which  are  analogous  with  seeds)  into  the  air  to  continue  the  existence 
of  the  species  elsewhere.  This  shows  most  clearly  the  funguB  (Asoo- 
myces  deformans),  which  was  working  suoh  mischief  in  the  leaves. 
You  will  now  see  what  is  the  matter  with  your  Peach  leaves ;  but  as  to 
the  cause  of  it  there  is  a  great  divergence  of  opinion.  The  majority  of 
scientific  men  regard  the  fungus  as  the  actual  cause  of  the  evil ;  the 
majority  of  gardeners,  on  the  contrary,  regard  it  as  the  results  of  a 
predisposing  cause — namely,  cold  winds  that  check  the  growth  of  the 
leaves  and  rupture  the  sap  vessels,  thus  providing  a  suitable  nidus 
for  the  germination  of  the  spores  of  the  corroding  parasite.  An 
excellent  gardener  has  written  : — “  Peach  blister  is  caused  by  the 
exposure  of  the  expanding  foliage  to  the  influence  of  frost  or  cold 
cutting  winds.  Here  are  a  few  examples  : — 1,  Upon  a  west  wall  every 
tree  is  perfectly  healthy,  with  a  free,  strong,  unchecked  young  growth 
clothed  with  fine  foliage,  perfectly  clear  and  quite  free  from  blister  or 
blemish  of  any  kind.  2,  Upon  a  south  outer  wall,  along  which  the  cold 
east  wind  swept  unchecked,  the  foliage  of  every  tree,  both  Peach  and 
Nectarine,  is  much  blistered ;  but  some  leaves  are  quite  sound,  and 
these  are  near  the  base  of  the  shoots,  and  have  had  the  shelter  of  the 
tips  of  surrounding  shoots.  Still  clearer  evidence  of  the  soathing  power 
of  the  cold  wind  is  gained  from  a  few  shoots  which,  springing  out 
farther  from  the  wall  than  the  others,  have  their  projecting  tips 
entirely  affected  by  blister — leaves,  leafstalks,  and  the  soft  young 
wood  itself  are  all  discoloured,  swollen,  and  contorted,  having  a  miserable, 
sickly,  gonty  appearance.  3,  Upon  a  south  inner  wall  all  the  trees  near 
the  east  end,  and  therefore  having  the  shelter  of  the  east  wall,  are 
quite  sound ;  but  further  on,  where  the  trees  are  more  exposed,  they 
are  affected  by  blister  precisely  in  proportion  to  the  extent  of  such 
exposure.  Cold  ungenial  weather  is  the  sole  cause,  and  we  have  the 
remedy  in  our  hands  by  planting  on  a  south-western  aspect,  and  by 
affording  suitable  protection  to  trees  in  more  exposed  situations.] 
