W58 

 LARKSPURS 



Delphi'nium spp. 



The native larkspurs are perennial, while those naturalized from 

 the Old World are annual. Some 60 native and 2 naturalized species 

 of larkspur occur on western ranges. Throughout the West this 



fenus is one of the best known members of the buttercup, or crow- 

 oot, family (Ranunculaceae) because some species are poisonous and 

 responsible for severe losses of cattle. Larkspurs are widespread, 

 one or more species occurring in every western State, Alaska, and 

 the Provinces of Canada. Larkspurs are common in the foothills 

 and mountains in the Western States, chiefly occurring in well-drained 

 loamy soil in mountain parks, grasslands, sagebrush areas, and in 

 clumps of aspen or in partial shade of other trees. The generic 

 name Delphinium is the Latin form for delphinion, a word used by 

 the old Greek botanist Dioscorides for larkspur. 



Many larkspurs are known to be poisonous to cattle, but it is ques- 

 tionable whether all species are poisonous under range conditions. 

 However, as Marsh, Clawson, and Marsh a have pointed out, it is 

 the safest policy to regard them all as suspicious pending full 

 knowledge concerning them. Horses and sheep have been poisoned 

 by forced feeding with certain species of larkspur but, under range 

 conditions, horses usually avoid these plants while sheep eat them 

 without injury. The greatest loss of cattle occurs during the early 

 spring and summer, because larkspur produces an abundance of 

 forage in advance of other plants and begins growth on the higher 

 summer ranges soon after the snow melts. This group creates a 

 serious problem in managing cattle on the range, because so many 

 larkspurs are poisonous both before and after blooming. Under 

 range conditions sheep are seldom poisoned by larkspur, and it is 

 common for sheep to utilize larkspur areas. The palatability for 

 sheep is considered good. 



In the treatment of poisoned animals beneficial results usually are 

 obtained by injecting a solution of 1 grain physostigmin salicylate, 

 2 grains pilocarpin hydrochloride, and 1/2 grain of strychnine sul- 

 phate, with a hypodermic syringe, preferably in the shoulder. 1 The 

 above amount dissolved in approximately 1 tablespoon of water is 

 the proper dose for an animal weighing 500 to 600 pounds. The 

 formula should be doubled for an animal of 1,000 pounds. The 

 syringe used in administering blackleg vaccine will serve. 



Numerous larkspur-eradication projects have been conducted in 

 the West, particularly with Barbey larkspur (D. barbeyi} and Sierra 

 larkspur (D. glaucum). Eradication has been attempted both by 

 grubbing and chemical means. In grubbing larkspur special care 

 must be exercised to assure that all plants, including the seedlings 

 and other small specimens, are dug. It is imperative that enough 

 of the root system be removed to prevent the remnant from sprout- 

 ing. This infers grubbing every larkspur plant discernible and 



1 Marsh, C. D., Clawson, A. B., and Marsh, H. LARKSPUR OR "POISON WEED," U. S. 

 Dept. Agr. Farmers' Bull. 988, rev., 13 pp., illus. 1934. Supersedes Bull. 531. 



