COCKLEBURS AS POISONOUS PLANTS 3 
Maiden, 1895, speaking of the Xanthium spinosum, which, in some 
localities is known as " Bathurst bur," quotes Doctors Bancroft and 
Goff, but adds nothing to preceding information. In 1896 Maiden 
quotes Prof. J. C. Arthur as stating in correspondence that in the 
United States the cockleburs do not have the reputation of being 
poisonous, and goes on to say that he is convinced that whether ex- 
tracts of the plant are poisonous or not it is not injurious in the 
field, and that he has investigated one case of supposed poisonous 
effect of Xanthium and found the trouble to be anthrax. 
Lewin, 1897, states that Xanthium splnosum in certain stages is 
poisonous and may kill 50 per cent of a herd. 
Bailey, 1898, referring to the supposed poisonous results from 
cocklebur, known in Queensland as " Xoogoora bur," states that in 
his opinion the plant would be dangerous only when making a rank, 
succulent growth. He describes it evidently from hearsay. 
Chesnut, in his preliminary catalogue, 1898, speaks of Xanthium 
canadense as killing hogs in Texas, X. strumarium as being fatal to 
the same class of animals in Georgia, and X. spinosum as being sus- 
pected of having poisonous properties. 
Halsted, 1889, says that the deaths of swine are attributed to Xan- 
thium, but while the effect may be mechanical, the plant does have 
poisonous properties. 
Kirk, 1901, makes the following statement : "At certain stages of 
growth the plant is poisonous to stock, but this is of little consequence 
as it is very rarely eaten by them." 
O'Gara, 1903, says there have been no cases of cattle poisoned in 
'Nebraska, but one farmer lost 20 hogs averaging 160 pounds each, 
and evidence showed that they had eaten a quantity of the young, 
juicy burs. O'Gara adds : " The whole plant, as well as the burs, is 
known to contain a poisonous principle which reduces heart action 
and causes death." 
Craig and Bitting, 1904, report that a chemical examination and 
a feeding test of Xanthium was negative. The young plants stripped 
of the burs were fed to calves, pigs, rabbits, and guinea pigs, but no 
untoward effects resulted, They state that post-mortems on animals 
supposed to have died from cocklebur poisoning showed that in all 
cases the death was due to the burs. "A few burs would be swallowed 
with the young plants and their horny prickles would irritate the 
stomach wall and cause inflammation which finally terminated in 
death. In three cases the burs lodged in the throat and could not be 
expelled." 
Stanley Coulter, 1904, says that cockleburs " are irritant on ac- 
count of the dust and hairs with which they are covered and not 
because of a toxic principle." 
Mayo, 1905, reported two serious losses of hogs from cocklebur. 
Out of 35 head, 25 died in one night, and 8 more during the next 
day. " They would lie down on their sides, kicking and pawing for 
a short time and then died." 
In an article in the Breeder's Gazette, 1908, Glint says that 
cocklebur is sure death to hogs, farmers sometimes losing 40 per 
cent, and that the plant will kill cattle in the spring. 
An article by King, 1909, states that young cockleburs are poison- 
ous to pigs. 
