Slough Borough Local Plan Site 20: Ditton Park Farm Slough, Berkshire. Agricultural Land Classification ALC Map and Report.

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1 Al Slough Borough Loal lan Site : Ditton ark Farm Slough, Berkshire Agriultural Land Classifiation ALC ap and Report April 997 Resoure lanning Team RT Job Number: 4/8/97 Eastern Region AFF Referene: EL /39 FRCA Reading

2 INTRODUCTION AGRICULTURAL LAND CLASSIFICATION REORT SLOUGH BOROUGH LOCAL LAN SITE : DITTON ARK FAR, SLOUGH. L This report presents the findings of a detailed Agriultural Land Classifiation (ALC) survey of 4. hetares of land to the south-east of Slough in Berkshire. The survey was arried out during April The survey was arried out by the Farming and Rural Conservation Ageny (FRCA) for the imstry of Agriulture, Fisheries and Food (AFF), in onnetion with the Slough Borough Loal lan. This survey supersedes any previous ALC information for this land. 3. The work was onduted by members ofthe Resoure lanning Team in the Eastem Region ofthe FRCA. The land has been graded in aordane with the published AFF ALC guidelines and riteria (AFF, 988). A desription ofthe ALC grades and subgrades is given in Appendix I. 4. At the time of survey the land on the site was in pennanent grassland. The areas ofthe site shown as 'Other Land' onsist of residential dwellings and a disturbed area with portaabins. SUAR. The findings ofthe survey are shown on the enlosed ALC map. The map has been drawn at a sale of :,. It is aurate at this sale, but any enlargement would be misleading. 6. The area and proportions of the ALC grades and subgrades on the surveyed land are summarised in Table. Table : Area of grades and other land Grade/Other land Area (hetares) % surveyed area % site area 3a Other Land N/A Total Surveyed Area Total site area N/A N/A 7. The fieldwork was onduted at an average density of boring every hetare. A total of 4 borings and soil pit were desribed.

3 8. The area to the westem side ofthe site has been mapped as Grade (exellent quality agriultural land). These fine and oarse loamy soils are deep, very slightly stony and fi-ee draining. Suh soils ombine with the prevailing limate to give land whih has very minor or no limitations to agriultural use. 9. The majority of the site has been lassified as Grade (very good quality agriultural land). The profiles are similar to those desribed above but are variable and sufferfi"oma slight wetness and/or droughtiness limitation depending on the ombination and harateristis of the soil horizons in eah profile. Oasional borings within this mapping unit are of worse quality.. On the south eastem edge ofthe site, the soils are impenetrable to the auger at varying depths. Although the soils are similar to the remainder of the site, the wetness and/or droughtiness restritions are more limiting whih restrits the land to Subgrade 3 a (good quality). FACTORS INFLUENCING ALC GRADE Climate. Climate affets the grading of the land through the assessment of an overall limati limitation and also through interations with soil harateristis.. The key limati variables used for grading this site are given in Table and were obtained from the published km grid datasets using the standard interpolation proedures (et. Offie, 989). Tabi : Climati and altitude data Fators Units Values Values Values Grid referene Altitude Aumulated Temperature Average Aimual Rainfall Field Capaity Days oisture Defiit, Wlieat oisture Defiit, otatoes Overall Climati Grade N/A m,aod day C mm days mm mm N/A TQ Gradel TQ Gradel TQ Grade 3. The limati riteria are onsidered first when lassifying land as limate an be overriding in the sense that severe limitations will restrit land to low grades irrespetive of favourable site or soil onditions. 4. The main parameters used in the assessment of an overall limati limitation are average annual rainfall (AAR), as a measure of overall wetness, and aumulated temperature (ATO, January to June), as a measure ofthe relative warmth ofa ioality.. The ombination of rainfall and temperature at this site mean that there is no overall limati limitation. Other loal limati fators suh as exposure and frost risk are not believed to have a signifiant adverse effet on the site. The site is limatially (jrade.

4 Site 6. The agriultural land at this site lies at an altitude of 9-m AOD. The majority ofthe land at the site is flat or very gently sloping with slight undulations. Nowhere does gradient or mirorelief affet agriultural land quality. Geology and soils 7. The published geologial information (BGS, 98) shows the majority ofthe site to be underlain with Flood-plain Gravel with a small area to the extreme north of the site being mapped as Taplow Gravel. 8. The most reently pubhshed soil information (SSEW, 983) shows the survey area to be mapped as 'unsurveyed, mainly urban and industrial areas'. However, the most likely Soil Assoiations to be found at the site are Hamble and/or Sutton. The former is desribed as 'Deep stoneless well drained silty soils and similar soils affeted by groundwater loally. The latter is desribed as 'Well drained fine and oarse loamy soils usually over gravel with a alareous matrix'. Soils broadly onsistent with the above desriptions were found upon field examination. AGRICULTURAL LAND CLASSIFICATION 9. The details ofthe lassifiation ofthe site are shown on the attahed ALC map and the area statistis of eah grade are given in Table.. The loation ofthe auger borings and pits is shown on the attahed sample loation map and the details ofthe soils data are presented in Appendb II. Grade. A limited area in the entral part ofthe site running along the most westem boundary has been lassified as Grade (exellent quality agriultural land). Typial profiles onsist of fine sandy silt loam topsoil overlying similar or slightly heavier upper subsoils whih are oasionally gleyed. Lower subsoils are variable in nature but generally onsist of heavy lay loam or lay with some sandy pokets also being observed. The profiles are generally stoneless or very slightly stony throughout (-% total flints, -% flints > m diameter). The depth to gleying varies from -48m whilst the soils beome poorly strutured and slowly permeable at depths between 68-78m where the layey horizons are observed. Drainage is therefore slightly impeded ausing a Wetness Class of II to be assigned to these soils. The light textured topsoils alleviate this minor soil wetness problem suh that Wetness Grade is onsidered appropriate. Soil pit is representative of these soil types. oisture balane alulations indiate that the available water apaity of the soils is suffiient to provide rops with adequate moisture to prevent drought stress in most years. This land therefore has very minor or no liniitations to its agriultural use. Grade

5 . The majority ofthe area is mapped as very good quality agriultural land (Grade ). The land is affeted mainly by droughtiness with soil wetness being equally or more restriting in plaes. The majority of profiles within this unit omprise very slightly to moderately stony (4- % total flints by volume, -% > m diameter) fine sandy silt loam or medium lay loam topsoils overlying similar or slightly heavier subsoils whih are sometimes gleyed (suggesting seasonal wateriogging). The soils are very variable depending on the amount of sand in the profile. However, the majority of profiles have poorly strutured slowly permeable lay, heavy lay loam or sandy lay loam horizons whih our at depths between 68 and 8m, some of whih ontain up to % total flints. Very oasional profiles were impenetrable to the auger at approximately 9m deplh over gravel. A wetness lass of I or n has been assigned to these soils depending on depth to slowly permeable horizons. On the whole, the ombination of soil texture and hard stone restrits the water available to rops suh that there is a very slight risk of drought stress to the plants in most years. This, sometimes in ombination with soil wetness (aused by slowly permeable subsoil horizons ourring at moderate depths whih affets rop growth and development and opportunities for landwork and/or grazing) restrits the land to Grade. Subgrade 3a 3. To the Southeast ofthe site, a smaller area of good agriultural land (Subgrade 3a) has been mapped. The prinipal limitations inlude soil wetness and soil droughtiness as in the Grade unit. 4. The areas affeted by soil droughtiness are those where moderate stone ontents within the profile restrit water availability to plants. Typially, these profiles onsist of fine sandy silt loam topsoils whih are very slightly to moderately stony (-% total flints, -% >m diameter). These pass to similar or slightly heavier upper subsoils whih have a maximum stone ontent of % total flints and are sometimes gleyed. The lower subsoils are again very variable ranging from loamy oarse sand textures to heavy lay loam. These lower horizons are gleyed but beome more gravelly with depth and impenetrable to the auger between -6m. A Wetness Class of I or II has been assigned to these soils. As in the (jrade unit, water availability to rops is restrited suh that there is a slight risk of drought stress to plants in most years. The risk is however, slightly greater than for land assigned to (jrade.. Those profiles affeted by soil wetness sufferfi"omimpeded drainage where the presene of slowly permeable layey horizons our at relatively shallow depths (3m). This impeded drainage gives rise to gleyed upper subsoil horizons (within 3m) as a result of seasonal waterlogging. The utilisation of the land is restrited by reduing the number of days when ultivations and/or grazing may our without ausing stmtural damage to the soil. This affet is partially offset by the light topsoil textures so that even though Wetness lass IV is assigned to these soils. Wetness Grade 3a is onsidered appropriate. Sharron Cauldwell Resoure larming Team, FRCA Reading.

6 SOURCES OF REFERENCE British Geologial Survey (98) Sheet No. 69, Windsor :, sale (Solid and Drift Edition). BGS: London. inistry of Agriulture, Fisheries and Food (988) Agriultural Land Classifiation ofengland and Wales: Revised guidelines and riteria for grading the quality of agriultural land. AFF: London. et. Offie (989) Climatologial Data for Agriultural Land Classifiation. et. Offie: Braknell. Soil Survey ofengland and Wales (983) Sheet 6, Soils ofsouth East England. :, sale. SSEW: Harpenden. Soil Survey ofengland and Wales (984) Soils and their Use in South East England Bulletin. SSEW: Harpenden.

7 DESCRITIONS OF THE GRADES AND SUBGRADES Grade : Exellent Quality Agriultural Land Land with no or very minor limitations to agriultural use. A very wide range of agriuiturai and hortiultural rops an be grown and ommonly inludes top fruit, soft fruit, salad rops and winter harvested vegetables. ields are high and less variable than on land of lower quality. Grade : Very (^od Quality Agriultural Land Land with minor limitations whih affet rop yield, ultivations or harvesting. A wide range of agriultural or hortiultural rops an usually be grown but on some land of this grade there may be redued flexibility due to diffiulties with the prodution ofthe more demanding rops suh as winter harvested vegetables and arable root rops. The level ofyield is generally high but may be lower or more variable than (jrade land. Grade 3: <jood to oderate Quality Land Land with moderate limitations whih affet the hoie of rops, the timing and type of ultivation, harvesting or the level ofyield. When more demanding rops are grown, yields are generally lower or more variable than on land in Grades and. Subgrade 3a: Good Quality Agriultural Land Land apable of onsistently produing moderate to high yields of a narrow range of arable rops, espeially ereals, or moderate yields ofa wide range of rops inluding ereals, grass, oilseed rape, potatoes, sugar beet and the less demanding hortiultural rops. Subgrade 3b: oderate Quality Agriultural Land Land apable of produing moderate yields of a narrow range of rops, prinipally ereals and grass, or lower yields ofa wider range of rops or high yields ofgrass whih an be grazed or harvested over most ofthe year. Grade 4: oor Quality Agriultural Land Land with severe limitations whih signifiantly restrit the range of rops and/or the level of yields. It is mainly suited to grass with oasional arable rops (e.g. ereals and forage rops) the yields of whih are variable. In moist limates, yields of grass may be moderate to high but there may be diffiulties in utilisation. The grade also inludes very droughty arable land. Grade : Very oor Quality Agriultural Land Land with severe limitations whih restrit use to permanent pasture or rough grazing, exept for oasional pioneer forage rops.

8 AENDIX H SOIL DATA Contents: Sample loation map Soil abbreviations - explanatory note Soil pit desriptions Soil boring desriptions (boring and horizon levels)

9 SOIL FROFH^E DESCRITIONS: EXLANATOR NOTE Soil pit and auger boring infonnation olleted during ALC fieldwork is held on a omputer database. This uses notations and abbreviations as set out below. Boring Header Information. GRID REF: national km grid square and 8 figure grid referene.. USE; Land use at the time of survey. The fouowing abbreviations are used: ARA: CER: OSR: OT: LIN: GR: SCR: DCW: HTH: Arable Cereals Oilseed rape otatoes Linseed ennanent pasture Srub Deiduous woodland Heathland WHT: OAT: BEN: SBT: FRT: LE: CFW: BOG: HRT: Wheat Oats Field beans Sugar beet Soft and top firuit Ley grass Coniferous woodland Bog or marsh Hortiultural rops BAR: ZE: BRA: FCD: FLW: RGR: OTH SAS: LO: Barley aize Brassiae Fodder rops Fallow Rough gih?;ing Other Set-Aside loughed 3 GRDNT: Gradient as estimated or measured by a hand-held optial linometer. 4. GLE/SL: Depth in entimetres (m) to gleying and/or slowly permeable layers. A (WHEAT/OTS); Crop-adjusted available water apaity. 6 B (WHEAT/OTS); oisture Balane. (Crop adjusted A - rop adjusted D) 7. DRT; Best grade aording to soil droughtiness. 8. If any of the following fators are onsidered signifiant, T' will be entered in the relevant olumn; REL: irorelief limitation FLOOD: Floodrisk EROSN: Soil erosion risk EX: Exposure limitation FROST: Frostprone DIST; Disturbed land CHE: Chemial limitation 9. LIIT: The main limitation to land quality. The following abbreviations are used; OC: Overall Climate AE; Aspet FR: Frost Risk GR; Gradient FL: Flood Risk TX: Topsoil Texture CH DR EX Chemial Drought Exposure WE; Wetness ER; Erosion Risk ST: R: D: WK: WD: Topsoil Stoniness irorelief Soil Depth Workability Soil Wetness/Droughtiness

10 Soil its and Auger Borings. TEXTURE: soil te.\ture lasses are denoted by the following abbreviations: S; Sand LS; Loamy Sand SL: Sandy Loam SZL: Sandy Silt Loam CL: Clay Loam ZCL: SiltyClay Loam ZL: Silt Loam SCL; Sandy Clay Loam C: Clay SC: Sandy Clay ZC : eat S L: eaty Loam S Silty Clay OL; Organi Loam Sandy eat L; Loamy eat eaty Sand Z: arine Light Silts For the sand, loam> sand, sandy loam and sandy silt loam lasses, the predominant size of sand fration will be indiated by the use ofthe following prefixes; F: Fine (more than 66% of the sand less than.nim) : edium (less than 66% fine sand and less than 33% oarse sand) C: Coarse (more than 33% ofthe sand larger than.6mm) The lay loam and silty lay loam lasses will be sub-divided aording to the lay : edium (<7% lay) H: Heavy (7-3% lay) ontent: OTTLE COL: ottle olour using imsell notation. 3. OTTLE ABUN: ottle abundane, expressed as a perentage of the matrix or surfae desribed: F: few <% C: ommon -% : many -4% V; very many 4% + 4. OTTLE CONT: ottle ontrast; F: feint - indistint mottles, evident only on lose inspetion D: distint - mottles are readily seen : promineni - mottling is onspiuous and one ofthe outstanding features ofthe horizon. ED, COL; ed fae olour using unsell notation. 6. GLE: Ifthe soil horizon is gleyeda''will appear in this olumn. If slightly gleyed, an *S' will appear. 7. STONE LITH; Stone Litholpgy - one ofthe following is used: HR; all hard roks and stones FSST: soft, fine grained sandstone ZR: soft, argillaeous, or silty roks CH: halk SST; soft, mediimi grained sandstone GS; gravel with porous (soft) stones SI: soft weathered GH: gravel with non-porous (hard) igneous/metamorphi rok stones Stone ontents (>m, >6m and total) are given in perentages (by volume).

11 8. STRUCT: the degree of development, size and shape of soil peds are desribed using the following notation: Degree of development WK; weakly developed ST: strongly developed edsize ed shape F; C; S: GR; SAB; L; fine oarse single grain granular sub-angular bloky platy D; : : AB: R: moderately developed medium massive angular b pnsmati 9 CONSIST; Soil onsistene is desribed using the following notation; L: loose VF: very fliable FR: friable F: firm V: very firm E: extremely firm EH: extremely hard. SUBS STR; Subsoil strutural ondition reorded for the purpose of alulating profile droughtiness: C; good : moderate ; poor. OR: Soil porositn. Ifa soil horizon has less than.% biopores >. mm, a T* will appear in this olumn.. I: Ifthe profile is impenetrable to rooting a T* will appear in this olumn at the appropriate horizon. 3. SL; Slowly pemieabl layer. Ifthe soil horizon is slowly permeable a T" will appear in this olumn. 4. CALC: Ifthe soil horizon is alareous, a ' will appear in this olumn.. Other notations: AW: A; BW; B: available waler apaity (in mm) adjusted for wheat available waler apaity (in mm) adjusted for potatoes moisture balane, va\eat moisiure balane, potatoes

12 SOIL IT DESCRITION Site Name : SLOUGH BL SITE it Number : I Grid Referene: TQ7B Average Annual Rainfall : 67 mm Aumulated Temperature : 49 degree days Field Capaity Level ; 39 days Land Use : ennanent Grass Slope and Aspet ; degrees HORIZON TEXTURE COLOUR STONES > TOT.STONE LITH OTTLES STRUCUJRE CONSIST SUBSTRUCTURE CALC - 8 FSZL R33 3 HR F 8-48 a R43 HR DCAB FR Ha V63 HR DCAB FR C yr6 HR WDVCL F 96- a V6 WDVCL F etness Grade ; Uetness Class Gleying SL II 48 m 78 on Drought Grade : AW : 3(nn A ; enin BW : B : 3 mm Rin FINAL ALC GRADE : AIN LIITATION :

13 program: ALCOl LIST OF BORINGS HEADERS ^/Ql/^l SLOUGH BL SITE page SALE ASEa WETNESS -WHEAT- -OTS- NO. GRID REF USE GRDNT GLEV SL CLASS GRADE A B A B.REL EROSN FROST CHE ALC DRT FLOOD EX DIST LIIT COftlENTS I TQ78 GR TQOO678 GR S 3 TQO778 GR 4 TQ678 GR TQ778 GR S S B WD DR 3A Ass roots 6 TQ878 GR 7 TQ78 GR 8 TQ678 GR 9 TQ778 GR TQ878 GR A DR 9 Ass roots see pit WE 3A Imp 9 DR DR 3A 6 Ass roots TQ6779 GR TQ7779 GR 3 TQ6778 GR 4 TQ7778 GR TQ777 GR A no A 3B DR WE 3A I 78 WD DR 3A Ass roots WD

14 program: ALCOl COLETE LIST OF ROFILES 3/7/97 SLOUGH BL SITE page SALE DETH TEXTURE COLOUR OTTLES ED COL ABUN CONT COL. STONES STRUCT/ SUBS GLE > >6 LITH TOT CONSIST STR OR I SL CALC I R33 OOOCOO F R43 63 R6 R6 7R6 6 R6e OOrtJOO HR HR HR HR 3 DCAB FR HDCAB FR WDVCL F WDVCL F Too porous With fine sand With fine sand mzl sl R4 R3 R46 R63 7R46 6 7R34 63 R R46 HR HR HR HR HR HR Border lay Dense, firm R43 R4 44 HR HR 4- R4 7R8 C HR Imp gravelly R3 R 7R46 C R3 R6 R63 DO R6 C R8 R6 7R8 OONOO OONOO HR HR -3 R4 DO HR 3-48 R3 HR R R6 R6 lorsa C 7R8 C 7R8 HR HR HR Firm R43 R43 R3 R3 lorsb F R8 C R6 OONOO HR HR HR HR Imp gravelly 7-3 R4 HR HR lorsl 6 R8 C lorss OOfWOO OONOO HR Loose, friable 8 - R4 HR sl msl 6 R6 C 6 6 7R R R8 OONOO HR Border lay Dense, firm Imp gravelly 9 - R4 HR R3 4 R R6 8 C R6 8 C oomoo oomoo HR HR HR 4 Loose, friable

15 program: ALCOll COLETE LIST OF ROFILES 3/7/97 SLOUGH BL SITE page SALE DETH TEXTiJRE COLOUR nui ilt;> COL ABUN ftu CONT COL. GLE > -:>iunto >6 LITH TO SUBS STR OR I SL CALC nl Is R3 4 R4 63 7R46 8 HR HR HR 6 8 Imp gravelly sl R R C R8 OONOO OONOO HR HR HR HR Loose Dense, firm R4 6 R8 H OONOO HR 4 Imp gravelly R43 OR3 R R8 C 7R8 OOmOO HR HR Finm, dense R33 3 R3 R6 C 7R8 OONOO KR HR HR Imp gravelly R4 DO R4 R63 R68 6 C R6 7R8 C 6 7R8 C OONOO OOWOO HR HR HR HR HR firm, dense

Wooodside Lane-Kings Stanley. Agricultural Land Classification. September RPT Job Number; ^/98

Wooodside Lane-Kings Stanley. Agricultural Land Classification. September RPT Job Number; ^/98 Wooodside Lane-Kings Stanley Agricultural Land Classification September 1998,-1 - \ Resource Planning Team Bristol FRCA Westem Region 37 RPT Job Number; ^/98 FRCA File No: EL14/1506 WOODSIDE LANE, KINGS