Am.  Jour.  Pharru. 
May,  1896. 
North  American  Coniferce. 
249 
work  the  trees  for  a  longer  time  than  four  years.  In  North  Carolina, 
the  smaller  land  owners  work  their  trees  for  eight  to  ten  successive 
seasons  or  more,  protect  the  trees  against  fire,  and  after  giving  them 
rest  for  a  series  of  years  apply  new  boxes  on  spaces  left  between  the 
old  boxes  with  good  results;  this  operation  is  known  as  reboxing  or 
back-boxing. 
The  process  of  turpentine  gathering,  as  just  described,  and  as  at 
present  carried  out,  is  almost  as  wasteful  a  one  as  could  be  devised. 
The  loss  by  evaporation  of  the  volatile  oil  alone  is  an  enormous  one. 
To  this  may  be  added  the  rapid  destruction  of  the  tree  for  turpen- 
tine purposes,  and  the  loss  by  fire  to  which  the  larger  surface  of  flow- 
ing resin  offers  especial  attraction. 
The  resin  taken  from  the  long-leaf  pine  at  least  comes  from  the 
sapwood  alone,  the  heartwood  being  impregnated  with  non-fluid 
oleoresin,  which  does  not  contribute  towards  the  flow.  The  resin 
tapped  is  not  only  that  which  was  deposited  in  the  sapwood  in 
former  years,  but  also  that  which  is  formed  during  the  years  of  tap- 
ping by  the  growth  of  the  tree ;  hence,  sufficient  amounts  of  active 
cambium  and  young  wood  should  be  left  untouched  to  permit  a 
plentiful  supply  of  water  from  the  ground  to  maintain  the  foliage  in 
vigor. 
Various  suggestions  have  been  made  to  accomplish  the  collection 
of  the  resin  in  accordance  with  the  conditions  just  mentioned, and  at 
the  same  time  prevent  the  waste  which  attends  the  American  system 
as  at  present  conducted.  The  Hugues  system,  as  conducted  in 
France,  possesses  many  advantages,  but  the  expense  of  adopting  it 
in  this  country,  and  the  fact  that  cups  are  required  instead  of  boxes, 
have  operated  against  it.  The  important  advantages  of  the  French 
system  are  that  the  chipping  is  more  slowly  and  carefully  conducted, 
that  this  chipped  surface  is  only  3  to  5  inches  in  width,  instead  of 
12  to  14  inches  as  with  us,  and  that  the  products  are  collected  by 
means  of  a  lip  or  trough  and  a  cup,  in  order  to  exclude  pieces  of 
bark  and  other  foreign  matter,  and  to  reduce  the  loss  by  evapora- 
tion to  a  minimum. 
At  the  recent  Cotton  States  and  International  Exposition  in 
Atlanta,  an  exhibit  was  made  in  the  U.  S.  Division  of  Forestry,  of 
a  process  patented  by  Mr.  J.  C.  Schuler,  by  which  no  boxes  are  cut, 
but  a  cup  of  iron  or  earthenware  was  substituted.  This  process 
may  be  understood  by  reference  to  Fig.  27. 
