AmjuJneTi8P76arm }      Tobacco  Culture  in  Pennsylvania.  257 
their  growth  without  interruption,  for  at  best  a  large  percentage  die, 
owing  to  want  of  sufficient  care  in  planting  or  the  ravages  of  the 
u  cutworm "  (different  species  of  the  genera  Agrotis,  Gortyna,  &e.)r 
which  is  the  principal  enemy  at  this  period  of  its  growth.  They  are 
concealed  in  the  earth  during  the  day,  and  go  on  their  errands  of 
destruction  at  night,  cutting  off  the  plant  while  it  is  young  and  succu- 
lent. The  only  means  of  preventing  the  ravages  of  this  enemy  is  to 
seek  for  him  in  his  hiding-place,  and  when  found  kill  him.  These 
belong  to  the  order  Lepidoptera,  or  scale-winged  insects. 
After  the  plants  have  been  thoroughly  rooted,  one  of  the  principal 
objects  is  to  keep  down  the  weeds,  which  grow  luxuriantly  in  the  rich 
soil.  This  is  accomplished  by  hoe-harrowing  and  the  hand  hoe  until 
the  plant  grows  too  large  to  admit  the  passage  of  a  horse  and  harrow 
without  injury  to  the  leaves,  after  which  the  plant  is  strong  enough  to 
suppress  the  weeds,  when  it  grows  very  rapidly,  soon  attains  the  height 
of  three  or  four  feet,  and  puts  forth  the  flowering  head.  This  is 
broken  off  when  leaves  are  the  object  of  the  cultivator,  but  whera 
seeds  are  desired,  the  inflorescence'  is  left  to  develop.  Cultivators  dif- 
fer as  to  the  proper  time  to  top  or  break  off  the  flower- head  ;  some  pre- 
fer to  top  when  the  stem  has  six  or  eight  leaves,  while  others  think  ten 
not  too  many.  After  being  topped,  axillary  branches  are  put  forth, 
which  are  popularly  known  as  "  suckers."  These  are  broken  off  as 
soon  and  as  often  as  they  appear.  The  whole  plant  is  now  covered 
by  a  viscid,  resinous  substance,  commonly  called  "  gum,"  which  ren- 
ders it  very  unpleasant  to  handle. 
About  this  time  tobacco's  greatest  enemy  makes  its  appearance, 
namely,  the  "  tobacco-worm  "  [Sphinx  Carolina,  Linn.,  different  spe- 
cies of  genus  Macrosilla  and  others).  This,  the  larva  of  the  "grey 
American  hawk  moth,"  is  a  green  worm,  sometimes  as  large  as  a  man's 
finger.  Allied  to  this  is  the  Sphinx  quinquemacu/ata,  of  Stevens  (also 
referred  to  Macrosilla),  the  larva  of  which  sometimes  infests  tobacco, 
but  more  frequently  the  tomato  and  potato.  These  moths  hide  them- 
selves and  sleep  during  the  day,  and  at  night  they  go  forth  to  deposit 
their  eggs,  in  patches  of  six  or  more,  on  the  leaves.  During  the  early 
hours  of  summer  evenings  they  may  be  seen  hovering  over  the  flowers 
of  the  "  Jamestown  weed "  {Datura  stramonium),  from  which  they 
extract  the  exuding  juice.  By  the  introduction  of  some  virulent  poi- 
son into  these  flowers,  numbers  of  them  might  be  destroyed.  These^ 
17 
