Vegetation of Northern Cape Breton. 



331 



scattered growth of annual and perennial herbaceous plants 

 which maintain a precarious foothold on the shifting sand. The 

 number of species in this latter zone is small, the only forms 

 noted here being Ammophila arenaria, Salsola Kali, Arenaria 

 peploides, Cakile edentula, Lathyrus maritimus, Euphorbia poly- 

 gonifolia, and Mertensia maritima. The lower and middle 

 beaches vary in width. On the South Pond spit, each is about 

 1 50 feet wide ; but ordinarily they are much narrower. The 



Figure 31. — Sand dunes with forest of white spruce, etc.; South Pond, 

 Aspy Bay. 



upper beach likewise varies in width; at South Pond it is fully 

 250 feet wide, but this is exceptional. At both North and South 

 Ponds the crest of the beach proper is perhaps four feet above 

 high water mark. At North Pond the upper beach is covered 

 by a broad, low dune which in places rises to a height of eight 

 or ten feet above high water mark. The plant cover here con- 

 sists mainly of a rank, open growth of Ammophila, with which 

 are associated Lathyrus maritimus and, locally, Elymus 

 arenarius. Over limited areas on the lea slope, the shrubs, 

 Myrica carolinensis and Rosa virginiana, have replaced the 

 Ammophila association. In one place a scrubby forest has been 



