Geoscience Reference
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F IG. 54
Medieval ridge and furrow at Upwood Meadows National Nature Reserve. Notice the reverse S shape
shown by the snow lying in the furrows. This shape was needed for turning the plough with teams of oxen
or horses. In summer, the better drained ridges are characterized by meadow buttercup, green-veined
orchids and anthills, while creeping buttercup, lady's smock and rushes grow in the hollows. (Photograph
T. C. E. Wells.)
The strips vary considerably in size but are commonly some seven yards (6.4
metres) from crest to crest and from one to three feet deep (0.3-0.9 m) from crest to
trough. On low-lying ground and heavy soils, water tends to lie in the hollows during
the winter, often for weeks at a time. The ridges, on the other hand, are better drained,
and the soil also tends to warm up more quickly especially on south facing slopes.
The pattern of soil conditions, repeated across a field, allows one to examine the ef-
fects, as shown in the following two examples, both from Sites of Special Scientific
Interest.
The first example is an elegant demonstration of the segregation of three closely
related species in a ridge-and-furrow meadow made by J. L. Harper at Pixey Mead,
near Oxford. This meadow was flooded most winters and had been continuously
mown for hay for at least 800 years. All three of the common grassland buttercups
occurred here, meadow buttercup Ranunculus acris , creeping buttercup R. repens and
bulbous buttercup R. bulbosus. A typical strip across the ridges and furrows showed
that bulbous buttercup occupied the highest ground whereas creeping buttercup flour-
ished in the bottoms of the furrows, and meadow buttercup was most abundant along
the sides of the ridges. Where the furrow was particularly prone to flooding, creeping
buttercup was 'pushed up' the sides of the ridges, meadow buttercup formed bands
along the tops, and bulbous buttercup was absent. In well-drained conditions, the re-
verse was found - meadow buttercup replaced creeping buttercup in the furrows, and
the tops of the ridges were free of buttercups altogether.
T ABLE 8
Plants recorded on 12 pairs of adjacent ridges and furrows at Wendlebury Meads,
Oxfordshire in May 1986. Numbers and species in 0.25 sq. m. quadrats. (Original
data B.N.K.D.)
Ridges
Furrows
Average no. species
15.2
4.7
Total no. species
40
14
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