Soil Associations

0811c HOLLINGTON

Soil and site characteristics

Deep stoneless reddish fine silty and clayey soils variably affected by groundwater. Flat land. Risk of flooding.

Geology

Reddish river alluvium

Cropping and Land Use

Stock rearing on permanent grassland.

Component soil series

Subgroup	Series name	Percentage	WRB 2006 link
8.11	HOLLINGTON	50%	Fluvic Eutric Gleysols
8.13	COMPTON	30%	Clayic Fluvic Eutric Gleysols
5.62	MATHON	10%	Fluvic Eutric Chromic Cambisols

Covers 104 km² in England and Wales

Soilscapes Classification

20	Loamy and clayey floodplain soils with naturally high groundwater

0811c HOLLINGTON

Detailed Description

Deep stoneless reddish fine silty and clayey alluvial soils of the Hollington association cover 97 km² in the Welsh Borderland, Wales, South West and Northern England. They suffer from winter and spring floods which severely restrict land use. Fine silty Hollington series, typical alluvial gley soils, are dominant but drier profiles of the Mathon series are common on the higher parts of the floodplains. Clayey pelo-alluvial gley soils, Compton series, formerly described as Woofferton series by Palmer (1972), often occur in low-lying places away from the rivers and are locally associated with wet silty, humose soils of the Dovey series. A key to the component series is given below. The association covers approximately 47 km² in the Welsh Borderland valleys of the Wye, Lugg and Severn. Most map separates are dominated by the Hollington series but occasionally other soils are more important. In the Lugg valley, north and east of Hereford, clayey soils of the Compton and Clyst series predominate on the broad meadows, with silty soils forming a minor constituent. In the hollows and old meander channels of Letton Lakes near Staunton-on-Wye, persistent waterlogging and consequent suppression of biological activity has caused the build-up of organic matter in surface horizons. Dovey series, morphologically similar to Hollington series, except in having humose, spongy topsoils are here included. Along the Severn the reddish alluvium becomes progressively more clayey southwards. Silty Hollington and Mathon series are important south of Worcester but downstream, north of Tewkesbury, clayey Compton soils predominate. Brownish soils are typical of the levees which have often been artificially raised by dredged material. Coarse loamy Alun and fine silty Teme soils occur here. In Wales the association is limited to 4 km². It floors a small valley draining the Devonian outcrop into Milford Haven and in eastern Dyfed it occurs by the Gwendraeth Fach near Porthyrhyd. Near Trecastle the association is mapped on swampy alluvium and Dovey soils are common.

The association covers approximately 30 km² in Devon, Somerset and Gloucestershire. Most occurs in north-east Devon and west Somerset along the upper Culm and Tone and several smaller streams. Along the river Creedy near Crediton the soils were formerly mapped in the Hellions complex. The river catchments encompass Permo-Triassic breccias, sandstones and mudstones and adjacent reddened Palaeozoic sandstones and slates. Hollington soils are dominant but there is considerable local variation in soil drainage, texture and colour. Fine silty Mathon and related fine loamy soils occupy levees and other raised ground on the floodplains, while Compton and Dovey soils are usually found in low-lying backlands. Sporadic bands of clay and gravel add diversity and redness is not always evident. Some calcareous soils occur near limestone outcrops at Westleigh. Elsewhere the soils are found along the river Severn near Tewkesbury. Here clayey Compton soils are a major component.

The association covers approximately 10 km² in north Cumbria on the floodplains of the rivers Waver and Wampool, which drain the till-covered lowland near the Solway Firth. It also occurs in alluvium derived from drift deposits overlying the St Bee's Sandstone near Whitehaven.

Soil Water Regime

Hollington and Compton soils, with their pronounced grey and ochreous mottling are variably affected by groundwater (Wetness Class IV or occasionally V in the wettest districts). The less mottled Mathon soils are affected by groundwater for shorter periods (Wetness Class II or III). Drainage improvement on the level land of this association is difficult because there is little outfall and water backs up the drains when river levels rise. The location of these soils flooring depressions in the floodplains coupled with their slowly or only moderately permeable profiles means floodwater may linger at the surface for some time during winter and early spring.

Cropping and Land Use

The association is almost entirely under permanent grassland because of the risk of flooding and the difficulty of working the wet, heavy soils. Hollows and old meander channels, particularly those with Dovey soils, are waterlogged for long periods, often well into the grazing season. Available water is adequate for grass growth during much of the year and many fields are valued for their good hay crops or for fattening livestock. Some of the Lugg meadows are still common land with a system of management largely surviving from medieval times whereby access is restricted in the spring until the hay is harvested, after which the land reverts to common grazing. Reseeding has to be carefully planned as soil conditions are not suitable every year. Reseeded swards poach easily as their bearing strength is much less than that of permanent grassland. Careful timing of grazing and management of stocking densities are therefore necessary to prevent newly sown grass from quickly degenerating into poor quality rush-infested pasture. In the Severn valley where flooding is generally a problem in winter and early spring and not during the main part of the growing season, some fields are under the plough and good crops of cereals can be grown. Autumn sowing is preferred as access during the spring is often limited by wet soils. Extreme caution has to be exercised when using heavy implements as weak surface bearing strength in wet conditions can lead to severe compaction and rutting. Deep cracks which usually form in these fine-textured soils during dry summers, aid drainage in the autumn until rewetting causes them to close but not usually before crops have been harvested. There is little data on the chemical fertility of Hollington soils but they are probably above average with no severe deficiencies. Cation exchange capacity is uniformly high and very high in surface soils where there has been a build-up of organic matter. Topsoils are usually slightly to moderately acid and soils are non-calcareous throughout. The wettest land provides important wildlife habitats which are becoming increasingly rare with the extension of field drainage. The negligible rate of outfall from some floodplain hollows to the watercourses make drainage amelioration prohibitively expensive so these areas can be usefully managed for wildlife conservation.

0811c HOLLINGTON

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

Midlands

Typical Landscapes

Midlands

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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 19/04/2024