Whorled Milkweed 
37 
the top of the hillside in Fig. 27. Water readily seeps out and 
keeps the hillside below rather moist beneath the surface. 
A glance at the soil conditions here will show the impractica- 
bility of cultivation methods. The prevalence of this condition in 
certain sections of the Western Slope led to the beginning of a 
series of experiments using chemical sprays. So far these experi- 
ments have yielded only negative results, but it is contemplated 
that the work will be carried on another season. 
Fig. 28 — The ditch above the hillside shown in Pig. 27. This gives an 
idea of the formation in which some of the milkweed occurs. 
SUMMARY 
1. Heavy losses of cattle, sheep, and horses on the Western 
Slope in Colorado have been due to Asdepias galioides, commonly 
called, in this State, the whorkd milkweed. 
2. This plant is pretty well distributed throughout the 
southern half of the State in irrigated sections from 5,000 to 
7,000 feet in altitude. 
3. Irrigation water, wind, railroads, and stock that are be- 
ing moved are probably the most important factors in the spread 
of milkweed by seed. 
