Golf Course Performance Standards (C)

9) Thatch depth: This is undesirable as the surface needs to be firm to influence green speed and uniformity of putt, as well as reduce the extent of ball/pitch marks and subsequent repairs and also the ability of a golfer to impart back spin onto a ball following initial contact with the green.

Thatch should be reduced to a very small amount, with typically a depth of maybe 3mm-5mm being desirable in contributing to sward resilience.

For a very good standard of green the depth might not exceed 6mm; whilst for a general standard the aim should be for no more than about 12mm.

Where thatch is 25mm or greater than this will be having a significantly negative impact on the surface and playing experience, although at certain times of the year when it is very dry this will not be as noticeable and visiting players may think that on the short time of their visit the green was actually good, but for much of the year this would not, typically, be the case.

The depth of thatch will help inform on the degree and frequency of scarification and verticutting needed, as well as whether any specific types of aeration work might be needed, for example, hollow-tining.

Thatch holds onto moisture, produces target golf, and results in significant ball marking, all of which is not beneficial if golfers are to improve their skill set. Thatch in tees and fairways should also be categorised and acceptable ranges might be given, for example:

• Tee: <6mm is good, up to 15mm being acceptable for general quality.

• Fairway: <8mm is good, up to 20mm being acceptable for general quality.

Firmness of surface is essential to allow for good foothold when teeing off and striking a shot form a fairway, so ensuring an appropriate threshold is set is a fundamental requirement for good golfing experiences.

10) Surface evenness: With the small size of a golf ball, it is essential that a smooth, uniform and even surface is provided to enable the ball to roll consistently along the anticipated line of putt.

A ball which deviates through no fault of the golfer will lead to complaints and questioning of the ability of the greenkeepers in producing a suitable golfing surface.

A measure of ‘trueness’ may therefore be inferred from surface evenness, or a separate measure may be made to determine ‘trueness’. A variation under a 3-metre straight edge of no more than ±3mm might be considered acceptable for high quality greens, but for more general quality greens this variation might be reduced to ±6mm.

For golf tees and fairways these parameters might be twice as great, i.e. ±6mm and ±12mm respectively for good quality to general quality surfaces.

Ensuring divots are regularly repaired to provide a uniform and smooth surface over which a ball rolls and bounces would significantly contribute to the maintenance of surface evenness.

11) Weed content: This can be a general indicator of all types of weed or one that has sub-categories of large-leaved weeds, small-leaved weeds, moss and algae.

A small amount of weed infestation shouldn’t be a particular issue for most greens. However, deciding on the parameters where action needs to be taken will relate to the extent of ‘pristineness’ wanted from a green.

For high quality greens a maximum small-leaved weed content of no more than 1% might be desired, ranging to no more than 10%, which might be acceptable for general quality greens. Large-leaved weeds would not be desired on any green and once noticed they would typically be hand weeded from the green.

Algae and lichen are not organisms that would be normally encountered on a golf green, so this parameter would typically be zero, whilst for moss this can be a particular problem on some greens, especially those which are enclosed by surrounding trees and hedges.

High class surfaces might aim for a maximum of no more than 0.5% moss content, whilst general quality greens might be no more than 3%, but local conditions for some greens might relax the criteria during the autumn and winter months to maybe 6% as a maximum.

Tees might have small-leaved weed content ranging from about 2% up to 10%, but large-leaved weeds would not be desired and even general quality tees may have a threshold as low as 2% only as a maximum content.

Fairways will vary in the extent of weed content that might be deemed acceptable as a maximum content, also being influenced on the type of course habitat, so small leaved weed content might range form no more than 5% up to no more than 15%, whilst for large leaved weeds this might be no more than 1% up to 5%.

12) Earthworm surface casting: Surface casts can affect the roll and pace of a ball and reduce the quality of the sward content. However, during the playing season, the amount of surface casting should be minimal as drier surface conditions will prevent or significantly reduce the activity of earthworms in the surface layer.

A small number of casts isn’t going to be a problem, but as the density of cast increase so will the problems and challenges in overcoming the negative effects of these.

In practice, the main periods for surface activity are out of season when it is cooler and when the soil is moist to wet. It is during this period that surface casts can smear when switched or brushed and start to smother some of the sward and provide a seed bed for weed species and annual meadow grass in particular.

On general quality greens a maximum coverage of 5% out of season might start to create issues with maintenance work, although with most greens being on a sandy soil this should not cause major problems to a greenkeeper, rather more a nuisance of constantly having to disturb the casts and redistribute them. For higher quality greens a figure of no more than 2% might be more appropriate.

The beneficial effects of earthworms within a soil, especially regards improved soil aeration and breakdown of organic matter should not be overlooked.