Geoscience Reference
In-Depth Information
No. of restricted species
31
5
Examples
Cuckoo flower
Cardamine
pratensis
Betony
Betonica officinalis
Meadow Fescue
Festuca praten-
sis
Dyer's greenweed
Genista tinctoria
Adder's-tongue fern
Ophioglossum
vulgatum
Soft rush
Juncus effusus
Creeping jenny
Lysimachia num-
mularia
Green-winged orchid
Orchis morio
Greater burnet
Sanguisorba officinal-
is
Creeping buttercup
Ranunculus
repens
The second example is from Wendlebury Meads, also in Oxfordshire. Here, the
soil is derived from a shallow layer of fine loamy drift overlying impermeable Oxford
Clay. The whole area is low-lying with a high water table and subject to prolonged
flooding in the furrows. The meadows have been grazed or cut for hay for 50-100
years or more. A sample survey of the vegetation across the centre of one field in
May 1986 showed striking differences in floristic richness between ridges and fur-
average number and total number of species there were significantly higher than in
the furrows. How far the floristically distinct communities correlate or interact with
distinct soil characteristics remains a topic for study.
The tendency towards agricultural improvement of soils has been mentioned
several times in this chapter. Most ridge-and-furrow grassland has been 'improved' in
the past 40 years through the use of herbicides and fertilizers, or has been ploughed
out altogether. Occasionally, the ghosts of ridge-and-furrow may appear briefly in an
arable field after a fall of snow, when small residual differences in soil conditions
cause the snow to melt in streaks. These cultivated soils form the subject of the next
two chapters.
