POISONOUS PROPERTIES OF BIKUKUEEA CUCUELA- 
RIA (DUTCHMAN’S-BREECHES) AND B. CANADENSIS 
(SQUIRREE-CORN) 1 
By O. F. Black, Chemical Biologist , W. W. Eggleston, Assistant Botanist , and J. W. 
KELLY, Chemical Laboratorian, Office of Drug , Poiso nous , and Oil Plant Investigations, 
Bureau of Plant Industry, United States Department of Agriculture, and H. C. 
Turner, Assistant Animal Husbandman, Virginia Agricultural Experiment Station 
INTRODUCTION 
Since the time of the early settlements in the mountains of Virginia 
frequent fatal cases of poisoning have occurred among cattle grazing in 
the mountain pastures in early spring. It has long been believed that 
certain early spring plants popularly known as “staggerweeds” have 
been the cause of these fatalities, since these plants are among the first 
to appear in the pastures and are often eaten by cattle when other forage 
is not abundant. Suspicion has chiefly centered upon the plants com¬ 
monly called larkspur {Delphinium tricorne Michx.), dutchman’s-breeches 
(Bikukulla cucullaria (L.) Millsp.), squirrel-corn (B. canadensis (Goldie) 
Millsp.), and wild bleeding heart {B. eximia (Ker) Millsp.). In the 
literature relating to poisonous plants the toxic character of D. tricorne 
has long been recognized, but the American species of Bikukulla appear 
to have received comparatively little attention from chemists and prac¬ 
tically none from toxicologists. 
The probable poisonous character of species of Bikukulla was first 
brought to the attention of the Department of Agriculture in June, 1920, 
by Prof. H. S. Stahl, of the Virginia Polytechnic Institute. He sub¬ 
mitted specimens of “little staggerweed,” later identified as Bikukulla 
cucullaria , with the statement that this plant was believed to be respon¬ 
sible for the recent death of a number of cattle in the mountain pastures 
of Bland County, Va. An extract of the plant prepared in the laboratory 
was found to be highly toxic, and in order to secure material for further 
study a representative of the department visited the locality where the 
cases of poisoning had occurred. At the request of Dr. A. W. Drinkard, 
jr., Director of the Virginia Agricultural Experiment Station, arrange¬ 
ments were made to conduct some cooperative experiments with a view 
to determine by feeding tests the effect upon cattle of the plant material 
collected for chemical examination. 
As a result of these investigations Bikukulla cucullaria has been shown 
to contain a poisonous alkaloid heretofore unrecognized, and the toxicity 
of this plant for cattle has been demonstrated. Poisonous alkaloids 
have also been found in B. canadensis , but this species is much less toxic 
than B. cucullaria and apparently is not likely to cause any damage to 
cattle. 
1 Accepted for publication Sept. 13, 1921. The plants referred to in the title are also known in bo¬ 
tanical literature under the following genus names: Dicentra, Bicuculla, Dielytra, Diclytra, Corydalis, 
Fumaria, and others. 
Journal of Agricultural Research, Vol. XXIII, No. 2 
Washington, D. C. Tan 13, 1923. 
aco Key No. G-262. 
(6y) 
