10 
BULLETIX 942, U. S. DEPARTMENT OF AGRICULTURE. 
EXPERIMENTAL WORK WITH A. VERTICILLATA VAR. GEYERI. 
A. verticillata, the whorled milkweed of the eastern part of the 
United States, is distributed throughout the Atlantic Plains and the 
Mississippi Valley. It differs materially from A. galioides, A, 
pumila, and A. mexicana in that it has long, fibrous roots and smooth 
pods. 
A. verticillata var. geyeri can be distinguished from the typical 
form by its numerous adventitious buds on the fibrous roots. These 
slender, fibrous budded roots are often long and horizontal and thus 
simulate the single strong horizontal roots of A. galioides. A. pumila, 
and A. mexicana. 
The material used in these experiments was collected at Missouri 
Valley, Iowa, on June 29, 1919. 
Thirteen feedings of this plant were made to sheep by the balling 
gun, resulting in two animals becoming sick and one other very sick. 
Three feedings with hay were made to a horse, with no result. 
The following table summarizes the experiments : 
Table 5. — Summary of feeding experiments with Asclepias verticillata var. 
geyeri (collected at Missouri V alley, Iowa, and air dried). 
Animi 
il. 
Weight 
of piant 
(esti- 
mated 
Designa- 
tion. 
Weight. 
Date of 
feeding. 
Method of 
feeding. 
Part of plant used. 
as green 
plant) 
for 100 
pounds 
of ani- 
mal. 
Remedy 
used. 
Result. 
Pounds. 1919. 
Pounds. 
Sheep 523 . . 
82 July 14 
Balling gun... 
Leaves and stems 
0.140 
None 
Not sick. 
Sheep 526 . . 
90.5 July 15 
do 
do 
.184 
do... 
Do. 
Sheep 527 . . 
82 
Julv 16 
do 
do 
.276 
do... 
Do. 
Sheep 544 . . 
95.5 
July 17 
do 
do 
.368 
do... 
Do. 
Sheep 556 .. 
98.5 
Julv 18 
do 
do 
.735 
do... 
Do. 
Sheep 548 . . 
103 July 19 
do 
do 
1.102 
do... 
Do. 
Sheep 540.. 
97 
July 20 
do 
do 
1.470 
do... 
Do. 
Sheep 473 . . 
114.5 
July 21 
do 
do 
2.205 
do... 
Very sick. 
Sheep 556 . . 
106 
Aug. 12 
do 
do 
2.021 
do... 
Not sick. 
Sheep 546.. 
89.25 
Aug. 22 
do 
do 
2.113 
do... 
Do. 
Sheep 552 . . 
97 
Sept. 20 
do 
Leaves and stems with 
large proportion of 
stems. 
Leaves 
2. 16S 
do... 
Do. 
Sheep 482 . . 
Sheep 523 . . 
129 
Sept. 23 
Sept. 25 
. do 
1. 2S6 
do... 
Sick. 
92 
do 
do 
1.470 
do... 
Do. 
Horse 126 . . 
995 
Julv 15-16 
Fed with hay. 
Leaves and stems 
.072 
do... 
Not sick. 
Horse 126 . . 
995 
Julv 17 
do 
do 
.15 
do... 
Do. 
Horse 126 . . 
995 
July 18-21 
do 
do 
.133 
do... 
Do. 
TYPICAL CASE OF SHEEP 473. 
Sheep 473 was a wether weighing 114.5 pounds at the time of 
the experiment. On July 21, 1919. between 4.05 and 4.37 p. m., it 
received by the balling gun. per 100 pounds of animal, 2.205 pounds 
of the plant, estimated as green plant. At 6.40 a. m., July 22, the 
pulse was 152, weak, but regular, and the respiration was deep. It 
seemed weak in the hind legs and sta££ered as it walked. 
