462 MANUAL OF POISONOUS PLANTS 



Poisonous properties. Chesnut and Wilcox say : 



Experiments have been made which show that at one stage of growth the leaves of 

 the species (D. Menziesii) may be safely eaten, to a certain extent, by sheep. Dr. S. B. 

 Nelson, professor of veterinary science in the Washington Agricultural College, in an article 

 entitled Feeding Wild Plants to Sheep, published by the Bureau of Animal Industry of 

 this Department, showed that it is possible to feed as much as 24J4 pounds of the fresh 

 leaves of D. Mensiesii to a sheep within a period of five days without causing any apparent 

 ill effects. The stage of growth of the larkspur was not stated, but, judging from the other 

 experiments described in the same report, it was probably in a well-advanced flowering 

 stage. 



In regard to the poisoning from this species, opinion seems to differ. Dr. 

 Nelson states that Dr. Wilcox was in error in regard to the plant that he 

 worked with at first. More than likely it was a D. bicolor, which is corroborated 

 by the report. Under D. bicolor, mention is made of D. Mensiesii. However, 

 it is more than likely there are certain stages in the development which are more 

 poisonous than others. Dr. S. B. Nelson from his experiments concludes as 

 follows : 



The results obtained in these eight trials with Delphinium Menziesii, the feeding of 

 nine and one-half pounds of the bulbs, stems and leaves of the immature plants to sheep 

 No. 6, the feeding of nearly twenty-five and six pounds of the plants gathered while in 

 full bloom, to Nos. 2 and 3 respectively, and the hypodermic injections of the two extracts 

 into Nos. 4 and S, certainly constitute evidence sufficiently convincing to justify the con- 

 clusion that Delphinium Menziesii is not poisonous to sheep and they may be allowed to 

 graze where it grows even in abundance without fear of any loss from it. 



Dr. Nelson likewise carried on an experiment with D. simplex with similar 

 results. 



Delphinium bicolor Nutt. Purple Larkspur 



A smooth or somewhat pubescent, tuberous rooted, perennial; 1-2 feet 

 high with a cluster of finely divided leaves; the lower orbicular in outline, all 

 deeply cleft or parted; racemes few or several-flowered; flowers dark purple; 

 sepals and spur ^ to 24 inch long; upper petals pale yellow, and white with 

 blue veins, follicles smooth or minutely pubescent when young. 



Distribution. Common in dry ground, Eastern Oregon, and Washington, 

 to Utah, British Columbia, Montana, and Colorado. Grows in elevations from 

 4000 or 5000 feet to 10,000 feet. 



Poisonous character. It is regarded as poisonous by stockmen. Experiments 

 reported by Dr. Wilcox in the Montana Agricultural Experiment Station Bulle- 

 tin show that an extract from less than one ounce of the dried leaves of this 

 species was fatal to a yearling lamb. Chesnut and Wilcox report further experi- 

 ments as follows : 



The following experiments were made with a view of ascertaining whether the per- 

 manganate of potash, which it was proposed to use in many cases of plant poisoning, 

 could be used with satisfactory results as a chemical antidote in case of this plant, and 

 also of determining which parts of the plant were most toxic. During some seasons the 

 purple larkspur causes extensive poisoning of sheep and calves. Cattle and horses, on the 

 other hand, seem to eat it less frequently than the tall larkspur. In the season of 1900 

 conclusive evidence against this plant was obtained in only one locality. This was derived 

 from two cases among calves in the Flathead Valley. The calves were about 5 weeks old, 

 and at the time when the poisoning occurred, were running in a native pasture where the 

 purple larkspur grew sparingly. The symptoms of poisoning in these two cases were sim- 

 ilar to those already outlined from poisoning in the tall larkspur in cattle, with the ex- 

 ception that a slight bloating was ten be observed in the case of the calves. The respiration 

 and heart beat became exceedingly rapid as the symptoms of poisoning increased in 

 severity. The body temperature was slightly lowered, and this was accompanied by pro- 



