Soil Analysis

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FAS offers a wide range of agricultural soil testing options for many crops. While our research has focussed on sugarcane for over 60 years, we can now offer soil analysis for tea and coffee, maize, sub-tropical fruit, macadamias, grain crops, gardens, nurseries, golf courses and bowling greens.

Soil analysis is important to optimise production while efficiently managing your resources. Regular soil testing enables the early detection of harmful soil conditions such as acidity and salinity build-up, nutrient imbalances and overloads, and the depletion of organic matter. It is thus a cornerstone of sustainable farming.

What We Offer

ANALYSES SA SADC Countries Other Countries
ROUTINE (SUGARCANE) Cost Per Sample
pH (CaCl2), phosphorus, potassium, calcium, magnesium, sodium, exchangeable acidity (Al+H), total cations, acid saturation, exchangeable sodium, zinc, copper, manganese, sulphur and volume weight. Estimates of clay and organic matter, potential nitrogen volatilisation, nitrogen mineralisation and reserve potassium.
(Fertiliser recommendations for other crops is given on request)
R242.00 R268.00 R308.00
SUBSOIL Cost per sample, first depth
Routine analysis for each depth. Includes a profile subsoil report with gypsum recommendations where subsoil analysis indicates excessive acidity. 242 268 308
Thereafter for each depth, cost per sample
R145.00 R163.00 R187.00
SOIL SALINITY AND SODICITY Cost per element per sample
pH; volume weight; exchangeable and saturation extract potassium, calcium, magnesium and sodium; electrical conductivity (EC); saturation %; sodium adsorption ratio (SAR); cation exchange capacity (CEC); salinity and sodicity status and gypsum recommendations. 245 247 284
Thereafter for each depth, cost per sample
103 103 118
SUPPLEMENTARY Cost per element per sample
R132.00 R152.00 R159.00
Maize
Corn
Veggies
Macs

Sampling Procedures (All Crops)

Topsoil Sampling Procedure

For routine topsoil analyses and fertiliser recommendations, samples should be collected using a Beater auger. Use of this auger ensures that a constant sampling depth is maintained (20 cm for sugarcane; 15 cm for most other crops) and allows for easy collection of a large number of subsamples. If interested please download our soil submission form.

Recommended sampling procedure:

Submission Form

Step One

s1

Avoid any obviously different patches of soil, examples are: anthills & old roads, filter cake, lime or fertiliser dumps, etc.

If the field consists of two distinctly different soil types, or only parts of the field have received large amounts of, for example, filter cake, a separate sample should be submitted from each section.

Step Two

s2

Because a very small amount of soil is analysed in the lab, it is vital that the sample submitted should be a good representation of the ‘average’ conditions across the field. For this reason, at least 30 – 40 subsamples should be collected from each field.

The subsamples should be taken in a zigzag pattern across the field. For ratoon crops, eight interrow subsamples should be collected for every one sample on the row.

Step Three

s3

Secure a sampling bag onto the top of the Beater auger bit.

Step Four

s4

Push the bit into the soil as far as it will go; this will ensure the correct depth of sampling. In hard or dry soils, press down on the auger with your foot to ensure that it is fully inserted to the correct depth.

Step Five

s1

Remove the bit from the ground. Turn the auger upside down and knock the bit with your hand or a stick until all the soil falls into the bag.

Step Six

s2

Continue to the next position in the field, and repeat the process. The sampling bag will naturally fold over, so that collected soil is not lost after sampling.

Step Seven

s3

Once the correct number of subsamples have been taken, they should be mixed thoroughly in the bag.

Step Eight

s4

Completely fill the FAS sample box with this mixed soil, and discard any soil that is left over in the sampling bag.

Step Nine

Fill in all the necessary details on the sample box, as well as on the soil sample
submissionform.

Subsoil Sampling Procedure

If subsoil acidity problems or any other subsoil nutritional problems are suspected, sampling to further depth should be undertaken before each replanting event.

Follow this recommended sampling procedure before submitting your soil sample:

Step One

11
a2

Soils should be sampled with a Dutch (screw type) auger marked off at 20 cm intervals.

Step Two

Ideally, samples should be taken to a depth of 80 to 100 cm, in increments of 20 cm (i.e. 0 – 20, 20 – 40, 40 – 60, 60 – 80 and 80 – 100 cm).

Step Three

Keep the samples from each depth interval in separate bags.

Step Four

Take three to four subsamples (borings) from random positions across the field.

Step Five

The subsamples for each depth interval must be placed into the appropriate sampling bag (e.g. all 0 – 20 cm subsamples will be combined into one bag).

Step Six

Mix the soil in each sample bag thoroughly and transfer into sample boxes.

Step Seven

The sampling depth should be clearly marked on the sample box. Thus there will be up to five sample boxes, each containing a composite sample from a certain soil depth.

Step Eight

Fill in all the necessary details on the sample box, as well as on the soil samplesubmission form.

Salinity and Sodicity Sampling Procedure

To assess a salinity or sodicity problem in soils, it is recommended that soil samples be taken for laboratory analysis.
This should be done to the recommended depth to ensure  that the source and extent of the problem is identified so that an appropriate reclamation strategy can be developed. Please use the correct Sample Submission Form.

Step One

Samples should ideally be taken with a Dutch (screw-in) auger, marked off at 30 cm depth increments.

Step Two

Sample at three depths (0 – 30, 30 – 60 and 60 – 90 cm), taking three to four samples from the field/area being investigated.

Step Three

In instances where there are patches of suspected salinity/sodicity in a field the suspected patches (usually indicated by poorer crop growth and sometimes salt accumulation on the soil surface) must be sampled separately from areas with better crop growth. Also collect three to four samples at the recommended depths from these areas.

Step Four

At each sampling site, place the 0 – 30 cm soil into one bag, the 30 – 60 cm sample into another bag and 60 – 90 cm into a third bag. Move on to the next sample site, and place the same depths into these bags.

Step Five

When three to four sampling sites have been combined, mix the samples thoroughly and submit them to the laboratory. There will thus be three boxes (for the three depths) from the well growing areas and three boxes for the poor growing areas. Remember to fill in the label on the sampling box, as well as the soil salinity sample submission form.

Step Six

If the area is irrigated, a sample of the irrigation water should be sent to the lab along with the soil samples. See Water Sampling Procedure.

Additional Information for Sugarcane Soil Sampling

  • Soil samples can be taken at any time during the year.
  • Samples should be taken from every replant field, and ratoon crops should be sampled after every second crop.
  • Collect the samples in good time so that they can be analysed and fertiliser purchased and applied before replanting (or ratooning).
  • Where fields are to be replanted, soil samples should ideally be taken after the second to last ratoon crop has been harvested. This allows sufficient time to plan and buy fertiliser and lime.

Contact Us

Mbali Shezi
FAS Admin Assistant
031 508 7474
fas@sugar.org.za

Drop Off Points

Find your nearest drop off point!

Soil Sample Submission

FAS soil sample boxes are available free of charge from every extension office.

Step One
Samples should ideally be taken with a Dutch (screw-in) auger, marked off at 30 cm depth increments.
Step Two
Sample at three depths (0 – 30, 30 – 60 and 60 – 90 cm), taking three to four samples from the field/area being investigated.
Step Three
In instances where there are patches of suspected salinity/sodicity in a field the suspected patches (usually indicated by poorer crop growth and sometimes salt accumulation on the soil surface) must be sampled separately from areas with better crop growth. Also collect three to four samples at the recommended depths from these areas.
Step Four
At each sampling site, place the 0 – 30 cm soil into one bag, the 30 – 60 cm sample into another bag and 60 – 90 cm into a third bag. Move on to the next sample site, and place the same depths into these bags.
Step Five
When three to four sampling sites have been combined, mix the samples thoroughly and submit them to the laboratory. There will thus be three boxes (for the three depths) from the well growing areas and three boxes for the poor growing areas. Remember to fill in the label on the sampling box, as well as the soil salinity sample submission form.
Step Six
If the area is irrigated, a sample of the irrigation water should be sent to the lab along with the soil samples. See Water Sampling Procedure.
Step One
11
a2

Soils should be sampled with a Dutch (screw type) auger marked off at 20 cm intervals.

Step Two

Ideally, samples should be taken to a depth of 80 to 100 cm, in increments of 20 cm (i.e. 0 – 20, 20 – 40, 40 – 60, 60 – 80 and 80 – 100 cm).

Step Three
Keep the samples from each depth interval in separate bags.
Step Four
Take three to four subsamples (borings) from random positions across the field.
Step Five
The subsamples for each depth interval must be placed into the appropriate sampling bag (e.g. all 0 – 20 cm subsamples will be combined into one bag).
Step Six
Mix the soil in each sample bag thoroughly and transfer into sample boxes.
Step Seven
The sampling depth should be clearly marked on the sample box. Thus there will be up to five sample boxes, each containing a composite sample from a certain soil depth.
Step Eight
Fill in all the necessary details on the sample box, as well as on the soil samplesubmission form.
Step One
s1

Avoid any obviously different patches of soil, examples are: anthills & old roads, filter cake, lime or fertiliser dumps, etc.

If the field consists of two distinctly different soil types, or only parts of the field have received large amounts of, for example, filter cake, a separate sample should be submitted from each section.

Step Two
s2

Because a very small amount of soil is analysed in the lab, it is vital that the sample submitted should be a good representation of the ‘average’ conditions across the field. For this reason, at least 30 – 40 subsamples should be collected from each field.

The subsamples should be taken in a zigzag pattern across the field. For ratoon crops, eight interrow subsamples should be collected for every one sample on the row.

Step Three
s3

Secure a sampling bag onto the top of the Beater auger bit.

Step Four
s4

Push the bit into the soil as far as it will go; this will ensure the correct depth of sampling. In hard or dry soils, press down on the auger with your foot to ensure that it is fully inserted to the correct depth.

Step Five
s1

Remove the bit from the ground. Turn the auger upside down and knock the bit with your hand or a stick until all the soil falls into the bag.

Step Six
s2

Continue to the next position in the field, and repeat the process. The sampling bag will naturally fold over, so that collected soil is not lost after sampling.

Step Seven
s3

Once the correct number of subsamples have been taken, they should be mixed thoroughly in the bag.

Step Eight
s4

Completely fill the FAS sample box with this mixed soil, and discard any soil that is left over in the sampling bag.

Step Nine

Fill in all the necessary details on the sample box, as well as on the soil sample
submissionform.