Report on a soil survey and agricultural suitability investigation of the property known as Erf 660, De Doorns.

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1 De Doorns erf 660 Soil Report 1 Report on a soil survey and agricultural suitability investigation of the property known as Erf 660, De Doorns. by F. Ellis September 2006 CONTENTS 1 INTRODUCTION AND TERMS OF REFERENCE 2 2 SURVEY METHOD 2 3 DESCRIPTION OF THE TERRAIN, GEOLOGY AND CLIMATE 2 4 SOILS 2 5 SUITABILITY FOR ANNUAL AND PERENNIAL CROPS 4 6 REFERENCE 6 APPENDIXES Appendix 1: GRONDOPNAME: DE DOORNS HOUSE ESTATE by D. Saayman

2 De Doorns erf 660 Soil Report 2 1. INTRODUCTION AND TERMS OF REFERENCE I was instructed by Mr. Nik Wullschleger of Boland Enviro, Worcester to investigate the agricultural suitability of the property known as Erf 660, De Doorns. The property is located next to the present residential area of De Doorns. The report was necessary for submission to the Department of Agriculture and Tourism, Western Cape Province, to be able to decide whether possible rezoning of part of the land could take place. 2. SURVEY METHOD Use was made of a soil map and report that was done of the whole property, known as De Doorns House Estate, by Mr. D. Saayman 1, a soil science lecturer at that time, during March Mr. Wullscheleger gave the soil map and report to me. After an investigation of the quality and detail of the information further fieldwork was considered unnecessary. In the Saayman report the soils were classified according to Soil Classification: A Taxonomic system for South Africa (Soil Classification Working Group, 1991) in SOIL FORMS and SOIL FAMILIES. 3. DESCRIPTION OF THE TERRAIN, GEOLOGY AND CLIMATE The property lies on a relatively level terrain, part of the alluvial/colluvial footslopes of the Hex River which forms the northern boundary of the property. The parent material from which the soils have developed consists of young alluvial deposits, except for a small area near the farmyard where shale forms the parent material The property is located in a winter rainfall area and experiences a mean annual rainfall of approximately 300 mm 4. SOILS Five soil mapping units (Fw/Du, Du1, Du2, Kd and Oa) were defined and their boundaries indicated on the map given in Fig. 1. A dam also occurs in the southeastern corner. The area earmarked for rezoning lies in the south and east of the farm and is indicated by means of a thick (red) line in Figure 1. A short description of each map unit, regarding dominant soils and properties is given in Table 1 below. 1 Grondopname: De Doorns House Estate deur D. Saayman, Maart 1994 (Map + report, see Appendix 1)

3 De Doorns erf 660 Soil Report 3 Table 1 Most important properties of map units Map symbol Dominant soils (Soil form/family) Brief description of terrain and soils Du 1 Du 1110 Orthic A horizon of about 20 cm thick on stratified alluvium layers of dominant medium sand texture on a grey to white sand with a medium pure sand from about 70 cm depth. Some signs of wetness visible in the deeper stratified layers Profile numbers that fall within or close to the demarcated area earmarked for the proposed housing development 21 Du 2 Du 1110 As for Du 1 but pure sand layer from cm depth 22, 23 Fw/Du Fw 1120 Orthic A on a light coloured E horizon, pure sand texture 20 Kd Kd 1000 Orthic A on a light coloured E (pure sand) on a gleyed loam 14 (On the Saayman map this part was included in the Du 1 unit) Oa Oa 2120 Orthic A (bleached, sand) on a sandy loam neocutanic subsoil 13 Dam Most important soil limitations for the growing of annual and perennial crops The soil properties that may limit root penetration and development, water and nutrient retention, aeration, and therefore affecting crop growth and production, can be one or more of the following: (these were taken into consideration for soil suitability evaluation purposes) 4.1 Surface crusting and hardsetting 4.2 Low clay content in topsoils and E horizons 4.3 Dense subsoil clay layers 4.4 Wetness 4.5 Underlying weathering rock 4.6 Coarse fragments in top and upper subsoils 4.7 High sand and/or silt content in topsoils 4.8 Free lime or salts 4.9 A shallow soil (shallow effective depth) The following classes and symbols were used (Table 2) to qualify the physical soil limitations of the map units in Table 3.

4 De Doorns erf 660 Soil Report 4 Table 2 Limitation classes and symbols used LIMITATION CLASS No limitation Slight limitation Moderate limitation Severe limitation ABBREVIATION (No symbol) Low Moderate Severe Table 3 Qualification of major physical soil limitations of mapping units Low clay content Topsoil Upper subsoil Wetness Density Low clay content Density Upper subsoil Lower subsoil of lower subsoil Coarse fragments Coarse fragments Map sym-bol Du 1 Moderate Low Moderate Low Low Du 2 Moderate Moderate Low Fw/Du Moderate Moderate Low Kd Moderate Moderate Low Moderate Low Oa Low Low Low Rock, saprolite or clay pan 5 SUITABILITY FOR PERENNIAL AND ANNUAL CROPS AREA SUITABILITY FOR PERENNIAL CROPS The specific area under consideration (based mainly on climate suitability) was rated MEDIUM HIGH suitability for especially table grape production by the Department of Agriculture, Elsenburg (Riglyne vir grondgebruiksbeplanning, Boland, 1989, Dept. Landbou & Watervoorsiening, Wintereënstreek, Elsenburg). This is at present also the preferred crop in the area. Most other crops potentially suitable for the area were given a rating medium to medium high. The rating given below for the soil therefore represents the maximum that can be obtained for perennial crops under the specified (climate, soil & terrain) conditions. SOIL SUITABILITY FOR TABLE GRAPES The suitability of mapping units for the production of table grapes grown under irrigation was rated in the field for all the profiles described by Saayman (1994). The subjective suitability rating ranges from 1 to 10, with 1 the lowest and 10 equal to the highest suitability. An interpretation of the rating system used for table production is given in Tables 4. The values given for each map unit are given in Table 6.

5 De Doorns erf 660 Soil Report 5 Table 4 Interpretation for wine grape production. Rating Suitability class rating Recommendation for table grape production Very Low Not Recommended Low Marginally suitable under special conditions* Medium Suitable High Recommended >8.0 Very High Highly recommended * Full irrigation, correct soil & viticultural practices and best management SOIL SUITABILITY FOR ANNUAL CROPS Annual crops include the normal cash crops (e.g. potatoes, vegetables & grain) that can produce a crop within one year. Pastures are not specifically included here but their suitability is expected to be slightly better that that of annual crops on all map units. Soil requirements for annual crops are generally lower than for perennial crops (i.e. soil depth is not so important although coarse fragments are more important) and manipulation of the soil is easier to compensate for possible problems. However, management is becoming very important to achieve success, especially if the soils are more marginal for use. It is assumed that irrigation water is available for production. Due to the low annual rainfall, sandy nature of the soil and the longer distance, compared to areas closer to Cape Town, the option for annual crop production is not very popular amongst farmers in this area. The same principal of rating as for the perennial crops was followed but the ratings were not done in the field but afterwards. The values allocated for each map unit are given in Table 5. Table 5 Interpretation for annual crop production Rating Suitability class rating Recommendation for annual crop production Very Low Not Recommended Low Marginally suitable Medium Suitable High Recommended >8.0 Very High Highly recommended By using the rating set out in Tables 4 and 5 above and applying it to the map units as given in Table 1, the final suitability per map unit for annual and perennial crop production is given in Table 6 below.

6 De Doorns erf 660 Soil Report 6 Table 6. Suitability of map units for annual and perennial (e.g. table grape) crops Map symbol Suitability for annual crops Suitability for perennial crops Rating for annual crops Field rating perennial crops Saayman s rating of table grape suitability for profile pit(s) within proposed housing area (average) Du 1 Recommended Recommended Du 2 Suitable Suitable Fw/Du Suitable Suitable Kd Suitable Suitable Oa Recommended Recommended According to this evaluation it can be seen that, using the ratings calculated for the map units, the proposed housing area has a medium to high soil suitability for the production of annual or perennial crops under good management including irrigation. However, using the ratings given by Saayman for the individual profile pits lying inside or adjacent to the proposed housing development zone, the ratings are on average lower than for the map unit as a whole. 6. REFERENCE SOIL CLASSIFICATION WORKING GROUP, Soil Classification: A Taxonomic system for South Africa. Mem. on the Agric. Natural Resources of S.Afr. No. 15.

7 De Doorns erf 660 Soil Report 7 Figure 1 Soil map of Erf 660, De Doorns as prepared by Saayman (1994) (Appendix 1). In this example the soil map overlies the airphoto of the area and was kindly prepared by Boland Enviro, Worcester

8 De Doorns erf 660 Soil Report 8 Appendix 1

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SOIL SURVEY REPORT ON SENCE de LIEU, PAARL

SOIL SURVEY REPORT ON SENCE de LIEU, PAARL April 2016 Report compiled by: B Schloms Pr. Sci. Nat. (registration Number 400059) Contents 1 Terms of reference 2 Allocation of responsibilities 3 Description