MARYLAND WEATHER SERVICE 211 



District. The Paw-Paw, the Wahoo, the Bladdemut and the Ked 

 Mulberry are infrequent along the Potomac and the Patapsco. 



Along the banks of streams the Buttonwood and the White Wil- 

 low are the most familiar trees. The shrubby willows are par- 

 ticularly abundant along stony shores and on the most low-lying 

 parts of the flood plains of the larger streams ; of them the Black 

 Willow is the most common except along the Potomac, where Ward's 

 Willow is equally abundant. 



The herbaceous flora of the Flood Plains shows a much closer 

 affinity with that of the moist soil-covered slopes than with the 

 sandy Flood Plains of the gravel soils of the Lower Midland or 

 the Flood Plains of the Coastal Zone. The numerous species, 

 sporadic in their occurrence, comprise characteristically the fol- 

 lowing : 



Spathyema foetida 

 Homalocench rus v irginicus 

 Adicea pumila 

 Thalictrum dioicum 

 Cardamine purpurea 

 Chrysosplenium a/mericanum 

 Rubus hispidus 

 Deringa canadensis 

 Chelone glabra 

 Gratiola virgin iana 

 Ranunculus sceleraius 

 Onoclea sensibilis 

 Lobelia puberula 

 Veronica americana 

 ( 'arex lupulina 

 ( 'arex bullata 

 Viola sagi (lain 

 Urticastrum divaricatum 

 Boehmeria cylindrica 

 < 'arex hiria 

 ( 'yperus strigosus 

 Elyinus v irginicus 

 Veratrum viride 



