86 BULLETIN" 365, U. S. DEPARTMENT OF AGRICULTURE. 
and climatic conditions may delay the time of blossoming, so that 
no arbitrary date can be given when a' range is safe. D. bicolor 
probably never grows in sufficient quantities to be dangerous as a 
poisonous plant. Inasmuch as the experimental work seems to show 
quite conclusively that sheep may feed upon larkspurs with entire 
impunity it is desirable in some cases, where there is an especial 
abundance of larkspur, to use the ranges for sheep rather than for 
cattle or to combine sheep grazing and cattle grazing in such a man- 
ner as to keep the areas of low larkspur eaten down by the sheep. 
