LARKSPUR POISONING OF LIVE STOCK. 7 
Eighth. By avoiding the areas where larkspur abounds during the months of 
April, May, and June the loss can be reduced to the minimum. 
Ninth. In potassium permanganate and atropin sulphate, respectively, we 
have a chemical and physiological antidote of real practical value. Stimulants 
are indicated. Tapping should be done with trocar and cannula high up on the 
left side, after first making slight incision on the skin with a knife. In case of 
extreme distention this operation should not be delayed. The value of bleeding 
is questionable. All measures which tend to depress the animal, such as 
forcible exercise, tobacco, aconite, etc., are positively harmful. If on sloping 
ground, the head should be turned up the hill. 
Crawford, 1907, quotes preceding authors in regard to the effect 
of larkspur upon stock, but adds nothing to what has been written 
before. Pammel, 1910, page 44, states that "cattle and sheep are 
most susceptible, although horses frequently suffer." 
Preceding the publication of the present general report on the 
larkspur investigation, there was issued in 1913 Farmers' Bulletin 
531, entitled " Larkspur or Poison Weed," which gave some of the 
practical results of the work. In 1915 Hall and Yates recapitulate 
the results of this bulletin, applying them to the larkspurs of 
California. 
It will be seen from the foregoing that up to the time when the 
detailed experiments of larkspur poisoning were undertaken by the 
Bureau of Plant Industry, a very definite body of evidence had been 
accumulated indicating that American larkspurs were poisonous to 
domestic animals, especially cattle and sheep, causing heavy annual 
losses in the mountain ranges. There was a fair amount of agree- 
ment in the descriptions of the symptoms of poisoning. The reme- 
dial measures recommended were very largely those worked out by 
Wilcox, and by Chestnut and Wilcox in their Montana work. There 
were, however, several questions with regard to the poisoning which 
for practical purposes had to be decided. In the published observa- 
tions and in the statements made by stockmen, the reports were 
somewhat contradictory with regard to which part of the plant is 
most poisonous, although there was a general agreement that the 
principal losses occur in the spring. It seemed necessary to deter- 
mine at what time of the year and under what conditions these plants 
are poisonous, to determine whether the tall larkspurs and the low 
larkspurs are equally poisonous, to describe in somewhat greater 
detail the symptoms of poisoning and pathological results, and to 
make further and more detailed experiments -upon the possibilities 
of using remedial measures to lessen the losses. There were also open 
questions concerning the best method of handling stock so as to pre- 
vent poisoning. 
It may be noted that practically all accounts of larkspur poisoning 
of stock in the United States relate to the mountainous regions of 
the West. As will be seen later in this paper, there is no reason to 
