Rorippa CRUCIFERAE Cardamine 



Var. hispida (Desv.) Butters & Abbe. (R. palustris var. 

 hispida (Desv.) Rydb.) 



Similar situations; infrequent, 



Armoracia Gaertn. 



A. rusticana Gaertn. Horse Radish. 



Escaped from cultivation, New Castle County. Introd. from 

 Europe. 



Barbarea R. Br. Winter Cress. 



B. vulgaris R. Br. (Incl. B. stricta Andrz.) Yellow Rocket. 



Damp ground, fields and roadsides; rather frequent in the Pied- 

 mont; less so on the Coastal Plain. Early May. 



B. veraa (Mill.) Asch. 



Common throughout, in fields and on roadsides. April. Introd. 

 from Europe. 



Dentaria L. Toothwort. 



D. heterophylla Nutt. 



Infrequent in rich woods of the Piedmont. Early April. 



D. laciniata Muhl. 



Common in rich woods of New Castle and Cecil Counties; rare 

 southward: roadside thicket 13^ mi. e. of Wattsville (Ac), A. V. 

 Smith & R. R. Tatnall, 4437, 28 April 1940 (T). Late April. 



Cardamine L. Bitter Cress. 



C. bulbosa (Schreb.) BSP. Spring Cress. 



Common in wet meadows of the Piedmont; one known collection 

 from the Coastal Plain: near Easton (Ta), Earle, 1411, 9 May 1937 

 (P). Late April, May. 



C. Douglassii (Torr.) Britton. (C rhomhoidea var. purpurea Torr.) 



Locally abundant in alluvial soil along the Susquehanna River: 

 "Cecil Co., Md.," J. J. Carter, 28 April 1887 (A); ^ mi. s. w. of 

 Rowlandsville (Ce), R. R. Tatnall, 4478, 6 May 1940 (T, P, A, G). 

 May. 



C. rotundifolia Mx. 



Infrequent in swampy places in the Piedmont area. May. 



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