14 
BULLETIN 1451, U. S. DEPARTMENT OF AGRICULTURE 
BORAX AND BORIC ACID 
The harmful effects of extremely small quantities of borax 
(Na 2 B 4 O7.10H 2 O) in fertilizers have been reported by Brown (3) 
and other investigators. In the fall of 1924 this chemical was tried 
in the greenhouse on barberries growing in 8-inch pots. To the 
surface of the soil in one pot was applied 5 grams and to another 
pot 1 gram of commercial package borax. To the soil in a third pot 
50 cubic centimeters of a saturated solution of boric acid (H 3 B0 3 ) 
was applied. This solution contained approximately 2 grams of the 
chemical. 
The effects of the chemical were slow in appearing, but within two 
weeks all the leaves of the plants receiving 5 grams of borax were 
dead. The plants in the other two pots had many dead leaves, but 
some leaves were still green. Two months after the treatment plants 
in all the pots were putting out new leaves, and three months after 
the treatment they were still growing. These results were not 
sufficiently satisfactory to warrant field treatments with borax and 
boric acid. 
CALCIUM CHLORIDE 
Calcium chloride has been used to some extent as a herbicide, and 
its similarity to sodium chloride in chemical composition suggested 
that it might be a valuable chemical for the purpose in hand. It is 
available in quantity, and its use as a road dressing to keep down 
dust and to hold the soil moisture makes it readily available in many 
sections of the country. A quantity of crushed, sacked calcium 
chloride therefore was obtained and treatments were made, parallel- 
ing in general those with sodium chloride. 
In the greenhouse it was found that 20 grams, or about the esti- 
mated equivalent of 4 pounds in the field, was sufficient to kill small 
barberries in 8-inch pots in 12 days. The cost of the chemical was 
about 1.5 cents a pound, so that it seemed worth while to continue the 
experiments in the field. 
Table 1. — Summary of treatments of individual, marked barberry bushes ivith 
calcium chloride 
Quan- 
Date of 
treat- 
ment 
Date of 
final ob- 
serva- 
tion 
tity of 
chemi- 
cal to 
the bush 
(pounds) 
•Method of application 
Bushes 
cut off or 
left stand- 
ing 
Location of 
area 
Bushes 
treated 
.- 
Bushes 
killed 
Per- 
centage 
killed 
1922 
1923 
Apr. 27 
July 3 
5 
Circle of 1-foot radius. . 
Cut off 
Gurnee,Ill.. 
20 
7 
35 
Do.... 
...do 
5 
do 
Standing.. 
do 
20 
9 
45 
Do„„ 
...do 
10 
do 
Cut off- 
do 
20 
16 
80 
Do.— 
...do 
10 
do 
Standing.. 
—do „ 
20 
16 
80 
Do— . 
—do 
15 
do 
Cut off- 
do 
20 
14 
70 
Do- 
...do 
15 
do 
Standing.. 
do - 
20 
15 
75 
July 10 
...do 
15 
Piled in base 
Cut off 
do -. 
20 
20 
100 
Do- 
...do 
15 
15 
do 
do.— 
Standing.. 
Cut off- 
do 
do 
20 
20 
20 
20 
100 
Oct. 16 
...do 
100 
Do- 
...do 
15 
do.. 
Standing.. 
do. 
20 
19 
95 
Total 
200 
156 
78 
