Soil Associations

0714c OAK 2

Soil and site characteristics

Slowly permeable seasonally waterlogged fine loamy over clayey and fine silty over clayey soils. Some similar soils with slowly permeable subsoils and slight seasonal waterlogging. Some clayey soils with chalky subsoil.

Geology

Chalky till

Cropping and Land Use

Winter wheat and other arable crops.

Component soil series

Subgroup	Series name	Percentage	WRB 2006 link
7.14	OAK	35%	Chromic Luvic Stagnosols
5.82	HORNBEAM	25%	Chromic Endostagnic Luvisols
7.12	RAGDALE	15%	Eutric Luvic Stagnosols
7.14	DUNKESWELL	10%	Chromic Alic Planosols
5.82	BATCOMBE	5%	Profundic Chromic Endostagnic Luvisols

Covers 97 km² in England and Wales

Soilscapes Classification

18	Slowly permeable seasonally wet slightly acid but base-rich loamy and clayey soils

0714c OAK 2

Detailed Description

This association covers 82 km² chiefly in Essex with an isolated area near Moreton-in-the-Marsh, Gloucestershire. The soils are mainly on flat hilltops, ridges or spurs and on the gentle upper slopes, often north-facing, of the adjoining valleys. In the main area west of Colchester the height ranges from 50 to 80 m O.D. on the relatively low south-east margin of the Essex plateau. The soils are dominantly fine loamy or fine silty with clay subsoils. They are non-calcareous and waterlogged in winter. They rest at depth on chalky till but most of the soils are deeply weathered and periglacially disturbed with aeolian silty drift mixed into the surface. The chalky till is usually at depths of over a metre and locally the drift has been decalcified to over 2.5 m depth (Allen and Sturdy 1980). The main soil, the Oak series with its clay loam upper horizons belongs to the paleo-argillic stagnogley soils and is associated with the Dunkeswell series, which is similar but has silty clay loam upper horizons. The clay subsoils are strongly mottled including red mottles formed under a relatively warm climate. These two soils cover about half the land area. The associated similar but better drained stagnogleyic paleo-argillic brown earths belonging to the Hornbeam and Batcombe series, have fine loamy and fine silty topsoils respectively with clay subsoils. Shallower soils with chalky till in the subsoil at less than 80 cm depth are less common. Of these, Ragdale series, pelo-stagnogley soils, is clayey to the surface, but similar Beccles soils with a fine loamy topsoil are common in some places. Better drained clayey Faulkbourne soils also occur. Small white chalk stones are characteristic of the subsoils of Ragdale, Beccles and Faulkbourne series.

The Oak series and its associated similarly deeply-weathered soils are found typically on the flat high ground. However, the upper surface of the underlying chalky till is uneven so patches of Ragdale, Beccles and Faulkbourne soils with chalky clay subsoil occur at random. These soils are, however, most common on lower slopes where solifluction has been most active. The upper loamy layers of these deeply weathered soils vary from almost stoneless to very stony. Flints are often concentrated in pockets at the base of the upper layers just above the clay subsoil which is usually slightly stony with large, angular flints. At Moreton-in-Marsh on a flat watershed of the Evenlode, Oak series is mainly accompanied by Beccles series with occasional Ragdale and Hornbeam soils. Most of the land near Moreton-in-Marsh is Oak series and the remainder mainly Beccles series.

Soil Water Regime

Slowly permeable clayey subsoils cause seasonal waterlogging in most of the soils. Oak, Beccles, Ragdale and Dunkeswell soils are seasonally waterlogged (Wetness Class III or IV) in the undrained state but can usually be improved to Wetness Class III by appropriate drainage measures. Hornbeam, Batcombe and Faulkbourne series, however, are naturally better drained and can be improved to Wetness Class II. In the dry climate of Essex, there are marked year to year variations in the incidence of waterlogging.

Cropping and Land Use

There is usually an adequate period for autumn cultivations in September and October. With good managment, minimum cultivations or direct drilling give winter cereal yields similar to those of conventional cultivations and enable large areas to be drilled quickly. In spring, opportunities for landwork are limited in average years and are negligible in a wet season even on the more easily worked Hornbeam, Batcombe and Faulkbourne soils. Spring wetness delays sowing so that spring barley rarely yields well. Sugar beet is now little grown because of poor establishment, difficulties in harvesting and damage to soil structure in wet autumns. Some potatoes are grown because of the nearness of London markets but the land is predominantly used for winter cereals. Cereals suffer moderately or slightly from drought but oilseed rape resists drought better because it matures earlier. Potatoes suffer moderately from drought and require irrigation for high yields. The soils are naturally acid and require occasional liming.

0714c OAK 2

Distribution Map

Note that the yellow shading represents a buffer to highlight the location of very small areas of the association.

Keys to component soil series

Eastern Region

Typical Landscapes

Eastern Region

Eastern Region

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Citation: To use information from this web resource in your work, please cite this as follows:
Cranfield University 2024. The Soils Guide. Available: www.landis.org.uk. Cranfield University, UK. Last accessed 08/12/2024