ERADICATING THE COMMON BAEBERKY 
33 
PETROLEUM FUEL OIL 
Petroleum fuel oil is a heavy oil obtained by the fractional distil- 
lation of petroleum. It was quoted at 7 cents a gallon and probably 
could be procured on short notice in most parts of the country at a 
very satisfactory price. 
No greenhouse tests were made with this substance, but the results 
of the field tests are given in Table 10. 
Table 10. — Summary of treatments of individual, marked, barberry bashes with 
petroleum fuel oil 
Date of i Date of final 
treatment j observation 
Quan- 
tity of 
chemi- 
cal per 
bush 
Method 
of appli- 
cation 
Bushes cut 
off or left 
standing 
Location of area 
• 
Bushes 
treated 
Bushes 
killed 
Per- 
centage 
killed 
Oct. 10,1921 
Oct. 8,1921 
Apr. 28,1922 
Do 
July 10,1922 
Do 
June 29,1923 
Oct. 12,1922 
July 3, 1923 
do 
do 
do 
Gallons 
1.0 
1.0 
1.0 
1.0 
1.0 
1.0 
Drench . 
—do-.. 
...do.... 
...do--.. 
...do.-.. 
—do.... 
Standing.. 
Cut off 
Standing.. 
Cut off— 
Standing.. 
Cut off— 
Black Earth, Wis. 
do 
Gurnee, 111 
do.. 
do 
do- 
10 
10 
25 
25 
20 
20 
6 
8 
15 
22 
15 
17 
60 
80 
60 
88 
75 
85 
Total. . 
110 
83 
75 
1 
An examination of Table 10 shows that there were but slight 
differences in the results of treatments in April, July, and October, 
^one of the treatments were very satisfactory, a fact apparently 
due to the failure of the oil to penetrate the soil any great distance. 
It spread over the soil but penetrated to a depth of only 3 to 4 
inches. Two years after the treatments the soil was still black and 
caked with the oil. Those portions of the barberry plants actually 
reached by the oil were killed in most instances, but sprouts de- 
veloped around the border of the area treated, and a few of the 
shoots which were actually reached by the oil were not killed. As 
with the other petroleum oils studied, the action of this oil was very 
slow. 
FURFURAL (FURFURALDEHYDE) 
Furfural ((CH) 3 OCCOH) is a thin, brown liquid with a not 
unpleasant, sweetish odor. It is made from oat hulls, corn husks, 
and other material. At present the supply is somewhat limited, 
and it sells for about 35 cents a gallon. With the development of 
uses for it, large quantities could easily be manufactured and the 
cost considerably reduced. 
In the greenhouse furfural appeared to be a very effective weed 
killer, as 2% cubic centimeters applied to the soil in 8-inch pots 
containing small barberries killed five out of six within two weeks 
after the application. Applications of large quantities killed all 
plants treated. 
Field trials were madeon three dates in the summer of 1924, and, 
as shown in Table 11, the results were very satisfactory. Applica- 
tions of 1 quart or more per bush were 100 per cent effective. 
