Am.  Jour.  Pharm. 
April,  19 1 7. 
}    Production  of  Lemon-Grass  Oil. 
187 
of  lemon  grass  tested,  a  heavy  growth  of  herb  with  high  oil  content 
is  to  be  expected  on  light,  well-drained  soil  of  the  high  pine  type. 
Time  of  Harvest. — Since  lemon  grass  is  a  perennial  crop  and  two 
or  three  cuttings  can  be  made  each  year,  it  is  of  interest  to  note  the 
difference  in  yield  of  oil  secured  from  the  plants  at  each  harvest.  In 
Table  IV  are  given  the  results  obtained  from  each  of  two  harvests 
for  various  years. 
Table  IV. 
Yield  of  Lemon-grass  Oil  Distilled  from  Plants  Harvested  at  Two  Different 
Times  of  the  Year. 
Year  and  Plants 
Harvested. 
First 
Second 
Harvest. 
Harvest. 
1908. 
Per  Cent. 
Per  Cent. 
0  31 
0-33 
.40 
.48 
Third  plat  
.20 
•35 
1912. 
No.  1  
.40 
.36 
No.  8  
.28 
.46 
1914. 
No.  1  
•37 
•  50 
No.  5  
•34 
•35 
No.  6  
.16 
.20 
Yield  of  Oil 
Year  and  Plants 
Harvested. 
1914  —  Continued 
No.  8   
No.  9  
I9I5- 
No.  1  
No.  8  
No.  9  
No.  10  
No.  11  
No.  12  
No.  13  
Yield  of  Oil. 
First  Second 
Harvest.  Harvest. 
Per  Cent. 
0.12 
.24 
.27 
.11 
.19 
•23 
.28 
.29 
.12 
Per  Cent 
0.38 
.36 
.26 
.11 
.17 
•47 
.40 
•31 
.27 
These  results  show  that  in  general  the  percentage  of  oil  is  higher 
in  the  second  cutting.  In  the  first  year  of  planting,  however,  the 
quantity  of  herb  obtained  in  the  second  cutting  is  much  less  than 
that  from  the  first  cutting ;  consequently,  the  acre  yield  of  oil  in  the 
first  year  would  be  greater  from  the  first  cutting  rather  than  from 
the  second. 
FACTORS  AFFECTING  THE  CITRAL  CONTENT  OF  LEMON- 
GRASS  OIL. 
Closeness  of  Cutting  the  Plants. — Experiments  conducted  with 
variety  No.  1,  grown  on  very  light  sandy  soil,  showed  that  the  citral 
content  was  highest  in  the  part  of  the  plant  nearest  the  ground. 
Large  plants  divided  into  three  portions  yielded,  on  distillation,  oil 
with  citral  content  as  follows :  Upper  portion,  70  per  cent. ;  middle 
portion,  78  per  cent. ;  and  lowest  portion,  82  per  cent.  A  similar 
test  made  with  variety  No.  5  divided  into  only  two  portions  yielded 
oil  with  citral  content  in  favor  of  the  lower  portion,  as  follows : 
