MUSTARD FAMILY CRUCIFERAE 
PURPLE SPRING CRESS. BITTER CRESS 
Cardamine Douglassii (Torr.) Britton 
In low rich woods in April or early May, the Purple Spring 
Cress or Bitter Cress may be found in bloom. It occurs from 
Maryland and Kentucky far north and northwestward along the 
Canadian Rockies to Arctic 
America. 
It is perennial by tuber- 
bearing underground stems, 
from which it comes up in 
masses over considerable areas. 
The slender stem is 5-12 inches 
high and may be somewhat 
hairy or entirely smooth. The 
basal leaves are borne on long 
slender petioles, whereas the 
stem leaves, 2-6, have short 
petioles or are sessile. They 
are usually toothed as shown 
but may be nearly or quite 
entire. 
The 4 sepals are purple 
tinged and the 4. petals are 
pale or rose-purple. The ma- 
ture pods are about 1 inch 
long and contain 2 rows of 
seeds separated by a partition. 
When ripe the halves curl up 
elastically from the base and 
the seeds may be thrown some 
distance. 
The Spring Cress, Cardamine bulbosa (Schreb.) BSP., is a similar 
plant which blooms 2-3 weeks later, in late May and early June, 
but its flowers are white instead of purple and it is usually found in 
more open swamps or other wet places. 
The Pennsylvania Bitter Cress, Cardamine pennsylvanica Muhl., 
occurs commonly on wet shores of ponds and stagnant waters as a 
much branched leafly plant 12 inches high. The small leaves have 
7-11 lateral and terminal leaflets, the terminal broad, ovate, and the 
oblong laterals tending to unite along the central axis. The white 
flowers are very small and the pods are erect on ascending pedicels. 
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