COMMERCIAL PRODUCTION OF LEMON-GRASS OIL. 
9 
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 tiro different times 
of the year. 
Year and plants har- 
vested. 
Yield of oil. 
Year and plants har- 
vested. 
Yield of oil. 
First 
harvest. 
Second 
harvest. 
First 
harvest. 
Second 
harvest. 
1908. 
Per cent. 
0.31 
.40 
.20 
.40 
.28 
.37 
.34 
.16 
Per cent. 
0.33 
.48 
.35 
.36 
.46 
.50 
.35 
.20 
1914— Continued. 
No.8 
Per cent. 
0.12 
.24 
.27 
.11 
.19 
.23 
.28 
.29 
.12 
Per cent. 
0.38 
No. 9 
.36 
Third plat 
1915. 
No.l 
1912. 
.26 
No. 1 
No.8 
No.9 
.11 
No.8 
.17 
No. 10 
.47 
1914. 
No. 11 
.40 
No. 12 
.31 
No. 1 
.27 
No.5 
No.6 
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: Upper 
portion, 74 per cent; lower portion, 76 per cent. These results show 
that the closest cutting which gives a profitable yield of oil also pro- 
duces a better quality of oil. 
Soil moisture. — Plants of variety No. 1, grown on soils having vary- 
ing degrees of moisture, yielded oil with citral content as follows: 
On dry sandy soil, 75 per cent citral: on slightly moist sandy loam, 
68 per cent; and on moist loam near the lake, 66 per cent. Further 
tests with other varieties on different types of soil have given similar 
