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 i inch 

 long and contain 2 rows ot 

 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 hulbosa (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 tound in 

 more open swamps or other wet places. 



The Pennsylvania Bitter Cress, Cardamine penmylvanica Muhl., 

 occurs commonly on wet shores of ponds and stagnant waters as a 

 much branched leafly plant 12 inches high. The small leaves have 

 7-1 1 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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