identifying soil structural problems in the...

Environment Agency thinksoils identifying soil structural problems in the field

Identifying soil structural problems in the field

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thinksoilsIdentifying soil structural problems in the field

Environment Agency thinksoils identifying soil structural problems in the field


56

sandy and lightsilty soilssandy and light silty soils

Environment Agency thinksoils identifying soil structural problems in the field / sandy and light silty soils


sandy and light silty soils

57

Environment Agency thinksoils identifying soil structural problems in the field / sandy and light silty soils / the soil surface


sandy and light silty soils / the soil surface

58

soil structure / the topsoil and cultivated layer

good structure

Sandy loam

High risk to slaking, runoff and erosion. Earlydrilling of cereals in September with good crop cover has helped to protect the soil surface.

The soil surface islocally slaked Partly slaked surface

Environment Agency thinksoils identifying soil structural problems in the field / sandy and light silty soils / the soil surface


sandy and light silty soils / the soil surface

59

soil structure / the soil surface

poor structure

Sandy loam

Lack of crop cover and a fine tilth hasexacerbated the slaking process. These soils arenaturally unstable due to their low clay andorganic matter content.

Evidence of runoff and soil movement

Slaked surface. Dispersed soilparticles have filled pores withfine sand and silt, forming a cap

Smooth soil surface that issealed, preventing rapidinfiltration of rain water

Environment Agency thinksoils identifying soil structural problems in the field / sandy and light silty soils / the topsoil


sandy and light silty soils / the topsoil

60

good structure

Sandy loam

Drilling of cereals at optimum soil moisture hasensured a good soil structure. Abundant rootshelp to stabilise the soil aggregates.

Very fine (<5mm) and fine (5-10mm) subangular blocks

Good rooting

Abundant pores allowing gooddrainage and aeration

Environment Agency thinksoils identifying soil structural problems in the field / sandy and light silty soils / the topsoil


sandy and light silty soils / the topsoil

61


poor structure

Sandy loam

Heavy traffic during harvesting of potatoes hascompressed the soil. Cultivation is needed toremove the compaction.

Very coarse (>10mm) plates High packing density

Firm soil strength Grey colouring indicating poordrainage and lack of oxygen

Environment Agency thinksoils identifying soil structural problems in the field / sandy and light silty soils / the subsoil


sandy and light silty soils / the subsoil

62

soil structure / the subsoil

good structure

Sandy loam

The low clay and organic matter content in thesubsoil has resulted in natural slumping,producing a poor soil structure. However, thesubsoil has many pores allowing good rootgrowth. Absence of mottles indicates a freedraining subsoil.

Friable soil strength

Weakly developed coarse(20-50mm ) subangularand angular blocks atbase of the cultivationlayer

Massive soil structureat depth with mediumpacking density

Low packing density. Soil is very porouswith good root growth

Environment Agency thinksoils identifying soil structural problems in the field / sandy and light silty soils / the subsoil


sandy and light silty soils / the subsoil

63


poor structure

Sandy loam

Compression of the wet soil by traffic andcultivation has produced a high packing density.Drainage and root growth are affected by thereduced porosity.

Massive soil Very firm soil strength

High packing densitythat is slightly porouswith few roots

Environment Agency thinksoils identifying soil structural problems in the field / sandy and light silty soils


sandy and light silty soils

64

medium soilsmedium soils

Environment Agency thinksoils identifying soil structural problems in the field / medium soils


medium

soils

65

Environment Agency thinksoils identifying soil structural problems in the field / medium soils / the soil surface


medium

soils / the soil surface

66


good structure

Clay loam

The clay content is sufficiently high to give somestability to the soil aggregates, preventingcapping of the surface.

No evidence of runoff Stable clods

Environment Agency thinksoils identifying soil structural problems in the field / medium soils / the soil surface


medium

soils / the soil surface

67


poor structure

Clay loam

Harvesting of maize has compressed the soilsurface causing ponding of rainwater. This hassubsequently caused the surface to slake andcap.

Evidence of pondingand runoff on slopes

Slaked soilforming a cap

Environment Agency thinksoils identifying soil structural problems in the field / medium soils / the topsoil


medium

soils / the topsoil

68


good structure

Clay loam

Soil beneath a hedge, with a high organic mattercontent and soil biodiversity.

Strongly developed soil structure

Fine (1-2mm) and medium(2-5mm) granular peds

Abundant fissures allowing gooddrainage, aeration and rooting

Environment Agency thinksoils identifying soil structural problems in the field / medium soils / the topsoil


medium

soils / the topsoil

69


poor structure

Clay loam

Compression of the soil has produced a highpacking density and slight porosity. Cultivation ofthe soil when the soil is suitably dry will help toremove compaction.

Coarse (5-10mm) plates

High packing densityMassive soil

Environment Agency thinksoils identifying soil structural problems in the field / medium soils / the subsoil


medium

soils / the subsoil

70


good structure

Clay loam over clay

Grey and reddish mottle colours in the claysubsoil indicate waterlogging for part of the year.When wet, the subsoil is at high risk ofcompaction from traffic.

Strongly developed soil structure

Good rooting

Friable soil with lowpacking density thatis very porous.

Medium (10-20mm)subangular blocks

Environment Agency thinksoils identifying soil structural problems in the field / medium soils / the subsoil


medium

soils / the subsoil

71


poor structure

Clay loam

The clay subsoil has been compressed by trafficand cultivation when the soil has been wet andplastic.

Massive soil Very firm soil strength and highpacking density that is slightly porous

Mottling indicates a seasonallywaterlogged subsoilFew roots

Environment Agency thinksoils identifying soil structural problems in the field / medium soils


medium

soils / the subsoil

72

heavy soilsheavy soils

Environment Agency thinksoils identifying soil structural problems in the field / heavy soils


heavy soils

73

Environment Agency thinksoils identifying soil structural problems in the field / heavy soils / the soil surface


heavy soils / the soil surface

74


good structure

Clay

The soil in this field is naturally acidic and is notas stable as calcareous clay soil.

No evidence of runoffPartly slaked soil

Environment Agency thinksoils identifying soil structural problems in the field / heavy soils / the soil surface


heavy soils / the soil surface

75


poor structure

Clay

These clay soils are slowly permeable and arewaterlogged for long periods. There are few daysin the autumn where landwork can be carried outwithout damaging soil, particularly in highrainfall areas.

Excessive runoff and soilwash depositing sedimenton gentle slopes

Environment Agency thinksoils identifying soil structural problems in the field / heavy soils / the topsoil


heavy soils / the topsoil

76


good structure

Clay

Abundant fine grass roots, earthworm activityand high organic matter have produced a goodsoil structure. Mottling indicates a naturallyslowly draining soil, although good structure willimprove drainage.

Very strongly developed soil structurewith compounds peds (where largerunits break into smaller peds)

Abundant fissures allowingdrainage, aeration and root growth

Secondary peds arevery fine (<5mm) andfine (5-10mm) sub-angular blocks

Environment Agency thinksoils identifying soil structural problems in the field / heavy soils / the topsoil


heavy soils / the topsoil

77


poor structure

Clay

Stock trampling in wet conditions hascompressed the topsoil, exacerbating poordrainage. The top half (where there is morebiological activity) has re-structured.

Very coarse (>10mm) plates withvery firm soil strength and highpacking density

Strongly developed soil structurein the top half with fine, mediumand coarse subangular blocks

Environment Agency thinksoils identifying soil structural problems in the field / heavy soils / the subsoil


heavy soils / the subsoil

78

17

17


good structure

Clay

Mottling indicates a slowly permeable subsoil.Naturally high packing density. High risk tostructural damage from traffic because of longperiods of waterlogged conditions.

Strongly developedsoil structure with coarse(50-100mm) and verycoarse (>100mm) prisms

Friable soil

Environment Agency thinksoils identifying soil structural problems in the field / heavy soils / the subsoil



79

18

18


poor structure

Clay

Naturally waterlogged subsoil with mottling. Thesoil has been compressed by traffic andcultivation in wet conditions. Improved landdrainage would help to reduce the risk of damageto the soil.

Very firm soil strength and highpacking density with few crop rootsVery coarse (>10mm) plates

Environment Agency thinksoils identifying soil structural problems in the field / heavy soils



80

chalk andlimestone soilschalk and limestone soils

Environment Agency thinksoils identifying soil structural problems in the field / chalk and limestone soils


chalk and limestone soils

81

Environment Agency thinksoils identifying soil structural problems in the field / chalk and limestone soils / the soil surface


chalk and limestone soils / the soil surface

82


good structure

Silty clay loam

An extremely calcareous shallow soil. The highsilt content makes the soil vulnerable to slaking.

Partly slaked, although thereare many cracks in the surface

Porous surface with no evidence of runoff

Environment Agency thinksoils identifying soil structural problems in the field / chalk and limestone soils / the soil surface


chalk and limestone soils / the soil surface

83


poor structure

Silty clay loam

Although the soil surface has capped there issome shrinkage and re-structuring due to thehigh clay and calcium content.

Compacted soil surface withslaking of the soil, forming a cap

Evidence of excessive runoffand deposition of sediment

Environment Agency thinksoils identifying soil structural problems in the field / chalk and limestone soils / the topsoil


chalk and limestone soils / the topsoil

84


good structure

Silty clay loam

The topsoil has a good soil structure that isstable due to the high calcium content that bindsclay particles together.

Very fine (<5mm) andfine (5-10mm) sub-angular blocks

Abundant pores withgood rooting

Environment Agency thinksoils identifying soil structural problems in the field / chalk and limestone soils / the topsoil


chalk and limestone soils / the topsoil

85


poor structure

Silty clay loam

The top half of the soil has been compacted dueto shallow cultivation in wet conditions.

Friable soil with mediumpacking density that ismoderately porous

Medium (10-20mm)angular blocks withmedium (2-5mm) plates

Environment Agency thinksoils identifying soil structural problems in the field / chalk and limestone soils / the base of the topsoil


chalk and limestone soils / the base of the topsoil

86

soil structure / the base of the topsoil

good structure

Silty clay loam over chalk

A shallow soil, where the chalk is less than 30cmdeep, that is naturally well drained.

Fragmented chalk

Friable soil with lowpacking density that isvery porous

Medium (10-20mm)and coarse (20-50mm)subangular blocks

Environment Agency thinksoils identifying soil structural problems in the field / chalk and limestone soils / the base of the topsoil


chalk and limestone soils / the base of the topsoil

87

soil structure / the base of the topsoil

poor structure

Silty clay loam

The base of the topsoil has been compacted. Thesoil sample was taken from the headland wherethere is more frequent farm traffic.

Firm soil strength withhigh packing densitythat is slightly porous Very coarse (>10mm) plates

Environment Agency thinksoils identifying soil structural problems in the field / chalk and limestone soils


chalk and limestone soils

88

peaty soilspeaty soils - uplandpeaty soils - lowland

Environment Agency thinksoils examining soils in the field / peaty soils

Examining soils in the field

peaty soils

89

Environment Agency thinksoils identifying soil structural problems in the field / peaty soils / upland peat / the soil surface


peaty soils / upland peat / the soil surface

90


25

25

upland peat / good structure

Peat

These soils are waterlogged for long periods. Theland requires careful grazing to avoid damagingthe soil structure.

No signs of damaged surfacefrom cattle or vehicles

No evidence of pondingor runoff

Environment Agency thinksoils identifying soil structural problems in the field / peaty soils / upland peat / the soil surface


peaty soils / upland peat / the soil surface

91


26

26

upland peat / poor structure

Peat

These soils are not capable of supporting out-wintered cattle because they lie wet for longperiods. They are easily poached and damagedby farm traffic.

Damaged soil surface causedby treading of livestock

Damaged soil surfacecaused by wheel ruts

Environment Agency thinksoils identifying soil structural problems in the field / peaty soils / upland peat / the topsoil


peaty soils / upland peat / the topsoil

92


Sandy peat

Sandy peat with a moderately developed soilstructure in permanent grassland.


Moderately developed, medium (10-20mm) subangular blocks.

Abundant fissuresallowing drainage,aeration and root growth

Environment Agency thinksoils identifying soil structural problems in the field / peaty soils / upland peat / the topsoil


peaty soils / upland peat / the topsoil

93



Sandy peat

A sandy peat that has been compacted by out-wintering of stock and farm traffic. The surfacereadily saturates, causing ponding and excessiverunoff on slopes, even under moderate rainfall.

Massive soil near the surface with veryfirm soil strength, high packing densityand slight porosity

Weakly developed, verycoarse (>10mm) plates

Environment Agency thinksoils identifying soil structural problems in the field / peaty soils / upland peat / the subsoil


peaty soils / upland peat / the subsoil

94

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Sandy peat over sandy loam

Sandy loam subsoil with thin naturally occuringironpan. The ironpan restricts water movementcausing waterlogging. Subsoiling can improvedrainage by disrupting the ironpan.

Moderately developed,fine (5-10mm)subangular blocks.Friable soil with lowpacking density that isvery porous.

Thin, impervious ironpan

Environment Agency thinksoils identifying soil structural problems in the field / peaty soils / upland peat / the subsoil


peaty soils / upland peat / the subsoil

95

30



Peat over sandy loam

Waterlogged most of the time due to highgroundwater table. Stock and traffic havecompacted the subsoil.

Waterlogged soil surfacewith drier subsoil

Firm soil strength with highpacking density andmoderate porosity Massive soil

Environment Agency thinksoils identifying soil structural problems in the field / peaty soils / lowland peat / the soil surface


peaty soils / lowland peat / the soil surface

96


25

25

lowland peat / good structure

Peaty loam

Skirtland soils, where the peat has degraded(due to ‘ wastage’), and where peat has beenmixed with the mineral clay subsoil, are more stable and are at less risk to wind erosion.

Rough and coarse seedbeds are at less risk towind erosion (although these are still vulnerablewhen the wind speed is greater than 20 mph).

A rough surface and largerclay content on ‘skirtland’ soilis at less risk to wind erosion

Very fine and fine granular soil,with medium and coarsesubangular blocks (10-50mm)

Environment Agency thinksoils identifying soil structural problems in the field / peaty soils / lowland peat / the soil surface


peaty soils / lowland peat / the soil surface

97


26

26

lowland peat / poor structure

Peaty loam

Bare peaty fenland soils are at risk to winderosion where the soil is dry and soil particles areless than 1mm diameter.

Dry fine soil with a looseconsistency has a high riskof wind erosion

Very fine and fine granular soilsurface. Soil has slumpedfollowing rainfall leaving asmooth surface

Environment Agency thinksoils identifying soil structural problems in the field / peaty soils / lowland peat / the topsoil


peaty soils / lowland peat / the topsoil

98


Peaty loam

Peay loam topsoil with good soil structure. The large organic matter content produces astable structure.


Very fine (<5mm) and fine (5-10mm)subangular blocks

Abundant fissures andpores with good rooting

Environment Agency thinksoils identifying soil structural problems in the field / peaty soils / lowland peat / the topsoil


peaty soils / lowland peat / the topsoil

99



Peaty loam

Peaty loam topsoil with poor soil structure alongcompacted wheelings.

Poor rooting with rootsgrowing through wormholes

Coarse angular blocks(20-50mm)

Very firm soil strengthwith high packing density

Environment Agency thinksoils identifying soil structural problems in the field / peaty soils / lowland peat / the subsoil


peaty soils / lowland peat / the subsoil

100



Peaty loam over silty clay

table and good soil structure accelerate peatwastage due to oxidation, shrinkage andconsolidation.

Well-structured peaty loam overlying a silty claymineral subsoil.

Agricultural land is highly dependent on artificialdrainage to lower the water table. A low water

Coarse (20-50mm)subangular blocks

Friable porous soil with roots

Mottled coarse angular(20-50mm) blocks withorganic material withinthe fissures

Environment Agency thinksoils identifying soil structural problems in the field / peaty soils / lowland peat / the subsoil


peaty soils / lowland peat / the subsoil

101



Deep cultivation and subsoiling can correct poor soil structure, provided the soil is dry enough andthere is an economic need.

Peaty loam over silty clay

Poorly structured peaty loam overlying silty clay.

Farm traffic in wet conditions can damage thesoil. Poorly structured soils have poor drainagewhich can lead to ponding and reduced cropyields. However, runoff is unlikely on flat fields.

Mottled very coarse(>100mm) prisms withstrong soil strength

Massive soil

Very firm soil strength andhigh packing density withno macropores

identifying soil structural problems in the...

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