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PravticaJ  Units  on  Vegetable  Fanning. 
Potato  Disease  (Phytophthora  infestans^.  — Tliis  disease 
requires  moisture  for  the  orowth  of  the  spores  Iviufi'  ou  the  leaf 
of  the  ])otato.  C-opper  sul])liatc  is  ])oisou  to  the  growing  s])ore, 
lieuce  the  henetit  of  s])rayinj>'  with  a solution  of  this  suhstanee. 
The  disease  is  spread  by  the  very  minute  spores  of  the  fungus 
floating);  in  the  air  and  carried  about  by  the  slightest  wind. 
The  conditions  under  which  the  disease  ap]>ears  are  the  satu- 
ration of  the  warm  atmosjdierc  in  the  late  sunnner  or  autumn 
with  water  from  heavy  rainfall,  and  the  liberation  when  the 
temperature  slightly  falls  of  a ])ortion  of  the  moisture  as  dew 
on  the  potato  leaf.  This  is  sufficient  to  cause  the  spore  to 
germinatt'.  When  the  delicate  tube  enun-ges  from  the  spore 
it  is  killed  if  the  leaf  has  been  sprayed  with  co])per  sulphate, 
hence  the  great  benefit  of  s])raying  with  dilute  Bordeaux 
mixture,  consisting  of  10  Ih.  of  co])])cr  suljdiate  (blue  stone) 
and  8 Ih.  of  freshly  slaked  lime  to  1()0  gallons  of  water.  The 
blue  stone  should  he  dissolved  in  warm  water  and  the  dissolved 
lime  should  be  added,  additional  water  being  poured  on  the 
lime  until  it  is  all  taken  up,  and  then  the  whole  may  he  made 
u])  to  100  gallons.  Wooden  vessels  should  he  employed  in 
these  operations.  The  mixture  should  he  used  as  soon  as  possible 
after  it  has  been  made,  as  it  deteriorates  by  keeping.  Where 
disease  has  already  obtained  possession  of  the  foliage,  the 
tubers  may  he  saved  by  moulding  up  to  a greater  depth,  and 
hv  cutting  off  the  haulm,  and  leaving  the  tubers  in  the  soil 
until  mature.  If  the  tubers  have  just  “set”  their  skins  I 
have  found  it  good  policy  to  lift  the  crop  and  store  them  away. 
Tomato  Diseases. — The  tomato  is  chiefly  affected  by  three 
diseases  which  attack  the  leaf,  the  stem,  and  the  fruit.  I^lants 
growing  in  a stagnant  and  com])aratively  cold  atmosjdiere,  and 
having  too  much  water  at  the  roots,  suffer  most  from  attacks 
of  leaf  disease*.  A warmer  temjeerature  and  freer  circulation 
of  air,  with  less  water  at  the  roots,  will  check  the  spread  of 
the  disease.  When  the  disease  first  makes  its  ap])earance  look 
to  the  above  details  and  coi-rect  any  defect,  and  at  once  sponge 
the  affected  leaves  with  a solution  of  sulphide  of  potassium 
(lime  of  sulphur)  in  the  jn-oportion  of  half  an  ounce  to  three 
quarts  of  water.  An  occasional  suhsecpient  spraying  with  the 
same  mixture  will  hold  the  disease  in  check. 
Another  disease  { Fnsarhnn  LycopersicI)  affects  the  stem  of 
the  tomato,  and  causes  the  ))lant  to  colla]»se  entirely.  Directly 
this  is  detected  remove  the  ])lant  bodily  with  the  soil  in  which 
it  is  growing  and  burn  the  whole.  Fill  up  the  hole  with 
