WOODLAND PLANTS 353 



planted, e.g. Spruce, Douglas Fir, and Larch ; the latter, 

 however, has deciduous leaves (see p. 275). In addition 

 to the heath-plants the following interesting species occur 

 in old Pine woods : Winter-greens (Pyrola minor, P. media, 

 and P. secunda) and Cow- wheat (Melampyrum), which are 

 semi-parasites ; the Coral-root Orchid, a saprophyte (see 

 p. 357), and Chickweed Winter-green (Trientalis europaea). 

 (2) Woodlands on calcareous soils : marls, limestones, 

 chalk. 



(a) Alder wood or Carr, with a ground flora of fen- 

 plants. The Alder is the dominant tree. Other 

 trees and shrubs are Sweet Gale, Creeping Willow, 

 Black and Red Currant, Berry-bearing Alder, Buck- 

 thorn, Guelder Rose, Common Ash, and Birch (B. 

 tomentosa). Common herbaceous species are : Marsh 

 Fern, Tussock Sedge, Yellow Iris, Nettle, Meadow- 

 sweet, and Marsh Marigold. 



(b) Oak- Ash wood on marls. These woods are similar 

 in many respects to the peduncled Oak wood, but 

 have a more varied ground flora. Oak and Ash are 

 the dominant trees. The shrub flora is abundant, 

 and consists of Hazel, Wayfaring Tree, Spindle Tree 

 (Euonymus), Traveller's Joy, Dogwood, Privet, Field 

 Maple. The characteristic herbaceous species not 

 found in the peduncled Oak woods are Herb Paris, 

 Meadow Saffron (Colchicum), Gladdon (Iris foeti- 

 dissima), Dog Violet (V. sylvestris), Nettle-leaved 

 Bellflower (Campanula Trachelium), and the Orchids 

 Helleborine media and H. purpurata. 



(c) Ash wood on limestone, the characteristic plants 

 of which have been given above, p. 349. 



(d) Beech wood on chalk. Native Beech woods are 

 confined to the Chalk Downs of the south of England, 

 where they form ' hangers ' on the steep slopes. 

 The deep shade cast by the Beech tends to exclude 



1296 Z 



