130 C. E. Moss, ]V. M. Rankin and A. G. Tansley. 
(b). Dry oakwoods. These occur on the drier “ siliceous ” 
soils above mentioned. The dominant trees are either the pedun¬ 
culate oak ( Quercns Robnr), or the sessile-fruited oak (Q. sessilijlora), 
which is especially dominant on shallow-soiled rocks, or finally a 
mixture of the two. Where the last condition occurs, hybrids 
between the two species are invariably to be found. 1 
As contrasted with the oakwoods on damp soils, the typical 
dry oakwoods are characterised by an absence of ash, a scarcity 
or absence of hazel (except apparently where planted), and an 
absence also of such shrubs as maple, sallow, dogwood, and guelder- 
rose. The birches, on the other hand, are characteristically strong 
(mainly Detain tonientosa, but also B. verrucosa and hybrids), and so 
is holly; while in south-eastern England, beech is also commonly 
present, and is locally developed in pure societies, as on the Barton 
Sands of the New Forest, on the Lower Greensand of Kent and 
Surrey, etc. 
In the hop districts of Kent, sweet chestnut ( Castanea sativa) 
is frequently met with on these soils in the form of pure coppice, 
e.g., on the Lower Greensand and on the Tunbridge Wells Sands, 
the last named geological formation bearing both damp and dry 
oakwoods, according to its local variations. The deep shade of 
chestnut coppice renders the soil beneath practically bare of 
vegetation, and the quickly drying surface forms an unsuitable 
nidus for vegetation even after the coppice has been cut. 
The soil of the dry oakwood is characteristically poorer in 
humus than that of the damp type ; and the herbaceous flora as 
well as the shrubby flora is much poorer in species. 
The primrose and other species which flourish on clays and 
loams are scarce or absent. Three of the most typical dominant 
ground species are the bracken ( Pteris aquilina), the wood soft-grass 
(Holcus mollis), and the bluebell (Scilla non-scripta).- The bracken 
and the bluebell also occur, as has been said, on the lighter loams 
of the damp oakwood type. 
Of other species characteristic of the dry woods, we may 
mention the wood sage ( Teucrium Scorodonia ), the tormentil 
( Potentilla erecta), the sheep’s sorrel ( Rumex Acetosella ), the wood 
anemone ( Anemone nemorosa), the upright St. John’s wort ( Hyper¬ 
icum pulchrum), the foxglove ( Digitalis purpurea), the rock bedstraw 
1 See Moss, “ British Oaks ” ; Journ. of Bot., Jan. and Feb., 1910. 
2 See T. W. Woodhead, Ecology of Woodland Plants in the 
Neighbourhood of Huddersfield. Journ. Linn. Soc. Bot., 
Vol. XXXVII., 1906, p. 333. 
