Perennial Peppergkass 
5 
III. Other Related Plants— The Perennial Peppergrass is a mem- 
ber of the mustard family and is a very close relative of the common 
field peppergrass (Lepidium apetalum L.) It is often confused with 
the less common species of this genus; especially Lepidium jonesii 
Rydb. and Lepidium scopulorum Jones which are also quite abun- 
dant upon the Western Slope and in the San Luis district. These 
resemble it somewhat in general appearance; especially in their 
shoAvy inflorescence. HoAvever, anyone who has had field experience 
Avith this plant has no difficulty in distinguishing it from either of 
these. Its characteristic spreading growth due to underground root 
stocks, its broad, whitish-pubescent leaves, the upper ones clasping 
the stem, its Avingless pod bearing, a long slender style, and its 
large broAvn seeds distinguishing characters of this plant. 
■4 
IV. Its Introduction and Distribution — Lepidium drab a L. is a 
native of central Europe and western Asia but is now quite com- 
mon throughout continental Europe and the British Isles. Its first 
appearance in this country AA-as noted about the seaports of New 
York, Washington and elseA\fiiere Avhich would seem to indicate that 
it has been carried into the United States on ballast or ship refuse. 
HoAA^ever, its almost simultaneous appearance in Colorado, Wyo- 
ming, and New Mexico suggests that it has also been carried into this 
country in foreign grown seed; possibly alfalfa seed. 
I At present its distribution in the United States is quite general 
I in local and restricted areas. It has been reported from most of 
I the eastern coastal states and a few of the central states such as : 
I Michigan, Wisconsin and Iowa. On the western coast, especially 
I in California, it is becoming a serious pest. However, in no localities 
I in the United States does it seem to be as pernicious as in the 
j Rocky Mountain region at altitudes from 4,000 to 8,000 feet. In 
Wyoming, Idaho, Colorado and New Mexico it is already a serious 
m pest in many districts. 
& It made its appearance in Colorado some twenty years ago. Its 
B presence in this state Avas first noted by C. S. Crandall who collected 
B specimens of this plant in 1898, growing in the vicinity of Palisade. 
B From there it has spread until now it is established in local areas 
m in most of the irrigated land of the state. Plate II shows its present 
R distribution in Colorado. The shaded portions of this map indicate 
B the parts of the state where this plant is found growing, but only 
B very restricted areas and sometimes only a few plants at a sta- 
B tion. It is especially troublesome in the Grand Valley and the San 
