Soil & Water Analysis

In order to ensure that the grass on a bowling grows well and remains healthily it is important that the Green keeper knows how to keep the soil in the best condition.

The science of soil management is a complicated matter and can be very off-putting to an inexperienced green keeper. Each time a green is cut or receives water; nutrients and trace elements are removed from the growing ecosystem. These need to be replaced; otherwise the growth of the grass will be impeded.

Given the current uncertainties regarding climate change it is the PH value of the soil can also alter in direct proportion to the amount of rainfall received. It is important to know the PH value of the greens soil as it also has a direct impact on the healthy growth of the grass.

In order to ensure what needs to be replaced the green keeper needs to know with some degree of accuracy what the soil conditions are like on each green.

There is, however a relatively simple solution to this problem and that is to have the soil analysed by a laboratory.

Where borehole water is used a sample of the water should also be analysed, since its make up will affect the quality of the soil it is being put on.

Once the results come back, there are essentially two options

  • Make the analysis yourself to determine the fertilization routine.
  • Get professional help to determine the fertilization routine.

If the latter option is taken then it is recommended that green keepers use Elsenburg College. Contact details are included on our Contacts page.

Soil and Texture

The texture of the soil on a green will have a major impact on the performance of the green.

It is important to know the texture of the soil on a green as this may have to be rectified at renovation time. It is equally as important to know the soil texture during the construction of a green.

A soil particle size analysis report should be carried out every 4 to 5 years.

Soils for good turf growth should consist of:

  • Good infiltration rate. Grass roots grow in-between particles of soil and use the soil to bind onto.
  • Good drainage. Too much water held around the roots results in starvation of oxygen causing damage.
  • Good aeration. Aeration depends on the air spaces between the particles as well as nutrients to pass freely in these spaces.
  • Adequate moisture and nutrient retention. Depending on the texture of the soil nutrients and water are stored between these spaces enabling the plant to obtain food over a period of time.
  • Absence of compaction. When particles of soil are too fine they bind together more easily and form compaction, thus resulting in poor drainage.

Compaction

Compaction mainly occurs between 35mm to 50mm below the surface layer. This must be dealt with immediately by means of drilling, hollow tining or verti-draining. Aqua-jetting is another method but is not advisable in certain soils.

The average forces exerted on a green by both machinery and players is typically as follows:

  • Standard mower 2 kg per square cm
  • Roller 1,8m (water) 2 kg per square cm
  • Bowler 5.7 kg per square cm
  • Roller polisher 0.7 kg per square cm

Soil Condition

In order to sustain good grass growth, certain microbes need to be maintained in the soil otherwise damage to the grass will occur.

It is important to ensure that any soil placed on the green is sterilized before application, as an unsterilized soil will likely bring in foreign grass and weeds.

It is advisable to order topsoil and river sand approximately 4 to 6 months ahead of the anticipated renovation period. Once the ratio mixture of topsoil and river sand has been established the soil can be mixed. Once this has been done it should be sterilized.

To sterilize soil the following methods can be done:

  • Lay the soil out on a firm base approximately 100mm thick, now wet the soil and immediately pour Herbifume on with a watering can then cover with Crop Guard cloth for fourteen days. (This method is expensive)
  • Lay soil on firm base where it will receive good sunlight. Wet the soil and immediately cover with a black plastic sheet. Leave for ten days and then remove all dead foreign matter. Repeat this for another ten days to ensure all foreign matter is killed. Before repeating turn soil. (This is a cheaper method)
  • Another method is once the soil is spread 100mm a good fire may be made on top which will burn all foreign seed remaining in soil.

Soil Sampling

In order to prepare a soil sample for chemical analysis a minimum of 6 cores should be removed from the green, trying to take the cores from different parts of the green. Once collected put all the cores from the green into a container and mix all samples and place in single packet, marked with the green, the date and time taken.

Should the Greenkeeper require a nematode analysis then a similar sample must be taken in addition.

Understanding what is going on below the surface is critical for successful turf grass management. Visual inspections, backed up with a professional analysis of soil properties, will give vital information about the condition of the soil and will help to produce a more productive environment for plant growth and sustainability.

A simple ‘visual, feel and smell’ inspection of a soil sample can identify many things:

  • Thatch content i.e. dead grass and fibre found in the top 5-35mmof the sample.
  • Dryness/wetness of soil (soil water content).
  • Soil compaction (lack of airspace in the soil).
  • Presence of black layer and algae.
  • Anaerobic conditions (indicated by a smell similar to rotten eggs).
  • Extent of soil layering (indicated by root breaks).
  • Root depth and vigour/
  • Pest and disease problems

The easiest way to make this inspection is by using a soil sampler. Samples should be taken once a year and once collected, sent away to a laboratory for a detailed analysis.

DO NOT SAMPLE WITHIN A MONTH OF FERTILISING.

The testing can reveal a lot of important data to help you diagnose any problems and to make an informed decision on future maintenance regimes.

The following five soil tests are normally performed:

  • Particle Size Distribution (PSD) soil classification (soil type).
  • Soil pH (acidity level of the soil).
  • Soil nutrient status.
  • Soil Organic Matter (OM) content.
  • Soil Toxicity.