14 BULLETIN 1012, U. S. DEPARTMENT OF AGRICULTURE. 
Efect of method of feeding—TIwo methods of feeding were used 
with the experimental animals, forced feeding with the balleg oun 
and feeding the plant mixed ane hay. 
Only two sheep, Nos. 564 and 578, were made sick by aotee the 
plant with hay. They were fed leaves: stems, and buds. The 
smallest effective dose of leaves, stems, aad bide when fed by the 
balling gun, is 1.096 pounds. The smallest dose of the two animals 
fed in hay was 0.284 pound in the case of Sheep 564. Apparently — 
the animals fed with hay were made sick on a smaller dosage. There 
is some doubt, however, in regard to the accuracy of the dosage fig- 
ures in the case of Sheep 564. Five head of cattle were given the 
plant in hay, with a minimum dosage of 0.264 pound. | 
Influence of aye of the plant.—lt was at first thought that the collec 
tions early in the season were somewhat more toxic than those 
obtained later. A careful examination of the cases, however, does 
not bear this out. So far as present evidence is concerned, then, 
the plant is nearly equally toxic at all seasons. 
Comparative toxicity of parts of the plant-—An examination of the 
dosage (Table 1) shows very clearly the extreme toxicity of the seed. 
The fruit heads stand next, while-there is no evidence to show any 
material difference in the toxicity of the other parts of the plant. 
It should be stated, however, that of course the weight of seed is of 
dry material, while the weights of the other parts of the plant are of 
green material. It would follow, then, that the difference between the 
toxicity of the seed and the other parts of the plant is not so great 
as the table indicates. 
Effect on different animals.—Only two classes of animals, cattle 
and sheep, were used in these experiments, and most of the sheep 
were fed by the balling gun. Comparing Cattle 861 and 863, which 
received leaves, stems, and young fruit, with Sheep 583, 590, 599, 
602, and 605, w ee were made sick on similar material, it appears 
that the plant i is about twice as toxic for cattle as for. an This, 
if true, is an interesting fact, but probably not of any especiat practi- 
cal importance, as uh Gres is no reason to think that is on the range 
eat much of this plant. 
“As a general statement regarding. the toxicity of Z. paniculatus it 
would probably be safe to say that, excluding the fruit and the seed, 
the toxic dose of the plant is beeen 1 aa 2 pounds per ince 
weight of animal. 
Fleming 3 gives as minimum toxic doses for yearling calves three- 
eighths of a pound, and with regard to sheep states that less than 
one-fourth of a pound rarely produces poisoning symptoms, and in a 
8 Annual Report of the Board of Control for the fiscal year ending June 30,1919. Agricultural Experi- 
ment Station, University of Nevada, Department of Range Management. 1920, pp. 42-43. 
