BULLETIN No. 77b. 
5 
Table I.—SHOWING THE INJURIOUS EFFECT OF SOLUBLE ARSENIC 
COMPOUNDS ON FOLIAGE, AND THE POWER OF LIME TO PRE¬ 
VENT SUCH INJURY. 
Medium of So¬ 
lution and 
Suspension 
453 Grams=l 
pound 
to 100 Gallons. 
Am’t of lime (CaO) in 1 
gal. mixture. 
Am’t of lime (CaO) in 
100 gal. mixture. 
Time mixture stood. 
Am’t of arsenic triox¬ 
ide (AS 2 0 3 ) in solu¬ 
tion in 1 gal. 
Am’t of arsenic triox¬ 
ide (AS 2 0 3 ) in solu¬ 
tion in 100 gal. 
Injuries to Foliage of 
Mulberry 
and Madeira Vines. 
Grams 
Grams 
Day 
Grams 
Grams 
r 
1 
.628 
62.8 
Scorched consid’bly. 
I 
1 
10 
4.098 
409.8 
All leaves destroyed. 
Water ... 
White arsenic 
9.06 
906 
1 
No injury.* 
9.06 
906 
10 
No injury. 
l 
4.53 
453 
1 
No injury. 
r 
1 
.574 
57.4 
Scorched consid’bly. 
10 
.595 
59.5 
Scorched consid’bly. 
Water_ 
London purple 
9.06 
906 
1 
No injury. 
i 
13.59 
1359 
1 
No injury. 
i 
4.53 
453 
1 
No injury. 
c 
1 
.066 
6.6 
Slightly scorched. 
W ater - -] 
Paris green_ 
10 
.081 
8.1 
Slightly scorched. 
4.53 
453 
1 
O J 
No injury. 
Bordeaux j 
Paris green._. 
1 
No injury. 
Mixture ( 
London purple 
No injury. 
* Burned on making second application. See discussion. 
The mixtures all contained 1 pound of the arsenite to 100 gallons. 
Bordeaux mixture was used as the medium of suspension in the 
last two experiments. Extensives applications of mixtures to foliage 
could not be made, as Madeira vines and mulberry leaves were the 
only suitable plants convenient to the laboratory. The effect in 
these two cases, however, is so strongly marked as to leave little 
doubt of what the effect on other foliage will be. In every case 
where there was soluble arsenic there was also “burning” of foliage, 
and this in all cases was in direct proportion to the amount of 
soluble arsenic. Where there was no arsenic in solution, there was 
no burning of leaves, except in the one case noted* in Table I, 
where white arsenic and lime had been standing only twenty-four 
hours. The application i'n this case was made in the same way as 
all the others—by sprinkling the liquid on the leaves. At the end 
of one week no injury was perceptible, when another application 
was made. In a few days the leaves were rather badly spotted with 
“burnt” places. I consider this due to the fact that all the white 
