Al Maidstone Borough Local Plan Site 13 The Tynme, Ashford Road Harrietsham Agricultural Land Classiflcation ALC Map and Report July 1994 AGRICULTURAL LAND CLASSIFICATION REPORT IVIAIDSTONE BOROUGH LOCAL PLAN SITE 13 LAND AROUND THE TYNME, ASHFORD ROAD, HARRIETSHAM 1 Summary 1 1 ADAS was commissioned by MAFF s Land Use Planning Unit to provide information on land quality for a number of sites in the borough of Maidstone in Kent The work forms part of MAFF s statutory input to the Maidstone Borough Local Plan 1 2 The site compnses approximately 3 hectares of land north of Ashford Road at Hametsham in Kent An Agncultural Land Classification (ALC) survey was camed out in July 1994 The survey was undertaken at a detailed level ofapproximately one bonng per hectare A total of 4 bonngs and one soil inspection pit were assessed in accordance with MAFF s revised guidelines and cntena for grading the quahty of agncultural land (MAFF 1988) These guidelines provide a framework for classifying land according to the extent to which its physical or chemical charactenstics impose long-term limitations on its use for agnculture 1 3 The work was camed out by members of the Resource Planning Team in the Guildford Statutory Group of ADAS 14 At the time of the survey the agncultural land on the site was under permanent grassland The land marked as urban includes a pnvate dwelling with garden and a derelict group of workshop buildings Areas marked as non-agncultural include some scmbland with mature trees and a track 1 5 The distnbution of grades and subgrades is shown on the attached ALC map and the areas are given in the table below The map has been drawn at a scale of 1 10 000 It is accurate at this scale but any enlargement would be misleading Table 1 Distribution of Grades and Subgrades Grade Area (ha) % of Site % of Agricultural Land 3a 19 57 6 100% Non-agncultural 03 91 Urban 1 1 33 3 Total area of Site 33 100% 1 6 Appendix I gives a general descnption of the grades subgrades and land use categones identified in the survey The main classes are descnbed in terms of the type of limitation that can occur the typical croppmg range and the expected level and consistency of yield 1 7 All ofthe agncultural land on the site has been classified as Subgrade 3a with soil droughtiness as the main limitation Soils on the site tend to compnse silty clay loams over chalk at varying depths The presence of chalk in the profile directly below the topsoii over much of the site means that there is a restnction on the amount of profile available water for plant growth with a consequent restnction on crop yields Therefore this land can be classified as no better the Subgrade 3a due to a moderate droughtiness limitation 2 Climate 2 1 The climatic cntena are considered first when classifymg land as climate can be ovemding in the sense that severe limitations will restnct land to low grades irrespective of favourable site or soil conditions 2 2 The mam parameters used in the assessment of an overall climatic limitation are average annual rainfall as a measure of overall wetness and accumulated temperature as a measure ofthe relative warmth ofa locality 2 3 A detailed assessment of the prevailing climate was made by interpolation from a 5km gndpoint dataset (Met Office 1989) The details are given in the table below and these show that there is no overall climatic limitation affecting the site 2 4 However climatic and soil factors do interact to influence soil wetness and droughtiness limitations Climatic vanables such as field capacity days and moisture deficits are at an average level for this site in a regional context Table 2 Climatic Interpolation Gnd Reference TQ 879528 Altitude (m AOD) 115 Accumulated Temperature 1374 °days Jan June) Average Annual Rainfall (mm) 748 Field Capacity Days 156 Moisture deficit wheat (mm) 105 Moisture deficit potatoes (mm) 96 Overall Climatic Grade 1 3 Relief 3 1 The site lies at an altitude of about 110-115 m AOD falling gently from north to south 4 Geology and Soils 4 1 The published geological information (BGS 1976) shows the entire site to be underlain by Cretaceous Lower Chalk 4 2 The published soils information (SSEW 1983) shows the site to be underlain by soils ofthe Coombe 2 association These are descnbed as well dramed fine silty soils over chalk or chalk mbble Shallow soils in places especially on brows and steeper slopes (SSEW 1983) Detailed field examination broadly confirms this 5 Agricultural Land Classiflcation 5 1 Table 1 provides the details of the area measurements for each grade and the distnbution of each grade is shown on the attached ALC map 5 2 The location of the soil observation points are shown on the attached sample point map Subgrade 3a 5 3 All of the agncultural land on the site has been classified as Subgrade 3a good quahty land with soil droughtmess as the main limitation Soil profiles typically compnse a very slighfly stony (2% total flints) medium silty clay loam topsoii and occasionally a similar textured upper subsoil which in tum overhes chalk A soil inspection pit (Pit no 1) was dug in the north ofthe site in order to assess the extent of rooting that occuned into the chalk Evidence of rooting was observed to a depth of 64cm I e 35cm into the chalk On this basis the profile available water for other soils over chalk on the site has been calculated The restncted rooting depths into the chalk and shallow soil depth over the chalk substrate means that there is a moderate droughtiness limitation in these soils which can restnct crop yields Therefore a classification of subgrade 3a is appropnate All of the profiles are well drained Wetness Class 1 It should be noted that some better quality land is present on the site yet It IS not sufficiently extensive to warrant mapping as a separate unit ADAS Ref 2007/158/94 Resource Plannmg Team MAFF Ref EL20/328 Guildford Statutory Group ADAS Reading SOURCES OF REFERENCE Bntish Geological Survey (1976) Sheet 288 Maidstone 150 000 Solid and Dnft Edition MAFF (1988) Agncultural Land Classification of England and Wales Revised guidelines and cntena for grading the quality of agncultural land Meteorological Office (1989) Climatic datasets for Agncultural Land Classification Soil Survey of England and Wales (1983) Sheet No 6 Soils of South East England I 250 000 and Accompanying Legend Soil Survey ofEngland and Wales (1984) Soils and their use in South East England Bulletin No 15 APPENDDC I DESCRIPTION OF THE GRADES AND SUBGRADES Grade 1 Excellent Quality Agricultural Land Land with no or very minor limitations to agncultural use A very wide range of agncultural and horticultural crops can be grown and commonly includes top fruit soft fruit salad crops and winter harvested vegetables Yields are high and less vanable than on land of lower quality Grade 2 Very Good Quality Agricultural Land Land with minor limitations which affect crop yield cultivations or harvesting A wide range of agncultural or horticultural crops can usually be grown but on some land of this grade there may be reduced flexibility due to difficulties with the production ofthe more demandmg crops such as wmter harvested vegetables and arable root crops The level of yield is generally high but may be lower or more variable than Grade 1 land Grade 3 Good to Moderate Quality Land Land with moderate limitations which affect the choice of crops the timing and type of cultivation, harvesting or the level of yield When more demanding crops are grown yields are generally lower or more vanable than on land in Grades 1 and 2 Subgrade 3a Good Quality Agricultural Land Land capable of consistently producing moderate to high yields of a narrow range of arable crops especially cereals or moderate yields of a wide range of crops including cereals grass oilseed rape potatoes sugar beet and the less demanding horticultural crops Subgrade 3b Moderate Quality Agricultural Land Land capable of producing moderate >aelds ofa narrow range of crops pnncipally cereals and grass or lower yields ofa wider range of crops or high yields ofgrass which can be grazed or harvested over most ofthe year Grade 4 Poor Quality Agricultural Land Land with severe hmitations which significantly restnct the range of crops and/or the level of yields It is mainly suited to grass with occasional arable crops (eg cereals and forage crops) the yields of which are vanable In moist climates yields of grass may be moderate to high but there may be difficulties in utihsation The grade also mcludes very droughty arable land Grade 5 Very Poor Quality Agricultural Land Land with severe limitations which restrict use to permanent pasture or rough grazing except for occasional pioneer forage crops 05 94 Urban Built-up or 'hard' uses with relatively little potential for a retum to agnculture including housing industry commerce education transport religous buildings cemetnes Also hard- surfaced sports facilities permanent caravan sites and vacant land all types of derelict land includmg mmeral workings which are only likely to be reclaimed usmg derelict land grants Non-agricultural Soft' uses where most ofthe land could be retumed relatively easily to agnculture including pnvate parkland public open spaces sports fields allotments and soft surfaced areas on airports Also active mineral workings and refuse tips where restoration conditions to 'soft' after-uses may apply Woodland Includes commercial and non-commercial woodland A distinction may be made as necessary between farm and non-farm woodland Agricultural Buildings Includes the normal range