224 
ST. ALBAN'S AND ITS NEIGHBOURHOOD. 
YI. FLORA. 
1. Phanerogamia. 
Although comprising some 58 square miles, the district dealt 
with in this brief review (viz., that within a five-mile radius 
of St. Albans Town Hall) is strikingly uniform as to the nature 
of its soil; this is, in the main, either gravel and sand or a stiff 
clay (brick-earth, clay-with-flints, or boulder-clay) overlying the 
Chalk, which, though not infrequently coming to the surface, 
never becomes exposed over any large area. 
The amount of calcareous soil is therefore relatively small, 
and the chief contrast to the clay is afforded by the sands and 
gravels. These owe their origin either to streams existing at 
the present day or whose beds were long since dry; or, in the 
case of the plateau gravels, are glacial in origin and frequently 
covered by a degradation product of sandy loam or clay. Peaty 
soil is one of the rarest types in the district, occurring only in 
one or two very restricted areas such as Colney Heath and 
Bricket Wood. 
Bearing in mind the limited area with which we have to deal, as 
we should expect, the climatic factor is not sufficiently variable 
to play any important part in determining the distribution of 
species. We must therefore turn our main attention to the 
edaphic, or soil conditions as being the main factors influencing 
the nature and constitution of our flora. 
A considerable portion of the land is under cultivation, either 
as pasture or as arable, mostly the former. 
Whilst the area of cultivation offers interesting problems both 
as regards the specific nature of its weeds and their distribution, 
yet the oecologist naturally finds his chief opportunities for 
study in the comparatively untouched woods and commons. 
The woods, as we should expect to find from the nature of 
the soil) are of the oak-hazel type, and the species of oak, 
that usually associated with clayey soil, viz.: Quercus robur 
( = Q- pedunculated) . The ground flora is chiefly comprised of such 
plants as the wood-anemone ( Anemone nemorosa) , enchantress’s 
nightshade (Circsea lutetiana ), lesser celandine ( Ranunculus 
ficaria), yellow dead-nettle ( Galeobdolon luteum), wild strawberry 
( Frag aria vesca ), ground-ivy ( Nepeta glechoma ), wood-sorrel 
(Oxalis acetosella) , wood-violet ( Viola riviniana), and Brachy- 
j -podium sylvaticum. Less frequently the buckwheat (Melampyrum 
pratense), wood-rush (Luzula vernalis), and primrose ( Primula 
acaulis ) are to be met with; whilst the teazle (Bipsacus sylvestris) 
and Millium effusum are distinctly local. 
Abundant forms in the more loamy woods are the pearlwort 
(Arenaria trinerva), woodruff ( Asperula odorata), and wood- 
sanicle ( Sanicula Europsea), and more locally the wood-sage 
( Teucrium scorodonia ) and foxglove ( Digitalis purpurea). The 
largest wood in the district is that known as Symond’s Hyde 
