Golf Course Performance Standards (E)

17) Pest damage: This will usually relate to damage caused to the surface and is primarily damage from leatherjackets and chafer grubs, and secondary effects of the grubs from birds pecking at the turf, or foxes or badgers digging for the grubs, but mammal damage is relatively uncommon. The threshold level for ‘acceptable’ damage might range from no more than 1% up to maybe 6% on the different surfaces, with greens being the least.

An indirect method of reducing the impact of damage is to firstly ensure root growth is relatively deep as grubs will only eat so much root. Also raise the height of cut slightly to encourage deeper rooting and to certainly reduce the thatch content as birds make more of a mess when this is present, and they also use this as bedding for their nests. This standard can therefore be influenced by numerous other standards.

Nematode damage can result in grasses becoming weak and more easily pulled out of a surface, although ground cover may still stay good. Nematode damage is relatively rare and may occur on very high sand specification green in particular where soil micro-organism diversity and quantity is significantly less than when compared with sandy soil greens.

18) Disease: A disease attack can make a sward look very unattractive, kill off some of the grass and take time to recover.

Creating conditions which provide a healthier, resilient (more stress free) sward are to be aimed for as this reduces the susceptibility of grasses to disease attack. A very low mowing height, being less than 5mm on greens, increases the stress exerted on a grass plant by reducing the leaf area available for photosynthesis, which also significantly impacts on root development. Disease can be categorised according to the severity of impact on a sward.

For example, Microdochium (Fusarium) patch disease can result in significant dead patches if allowed to rapidly spread, so no more than 2% coverage might be a threshold for action on high quality surfaces, but up to 5%, on general quality greens might be acceptable.

By contrast red thread disease, which can be classed as a cosmetic nuisance disease, might have maximum parameters ranging from of 5% up to 10%, depending on quality requirements. Tees and fairways would typically have slightly higher threshold figures.

In general though, the different types or severities of disease impacts are grouped under disease content and represented as a maximum percentage within a sward.

19) Surface colour: In general, a darker green appearance is desired, but uniformity of the colour is just as important, if not more so, because a patchy surface will certainly impact negatively on presentation: Grass will naturally vary in colour throughout the year and during the drier summer months a lighter straw green colour will be quite natural for a fescue-bent sward.

A lighter green sward can be readily darkened by a light application of sulphate of iron or nitrogen foliar feed, if desired.

Different grasses will also appear slightly different in greenness so the type and extent of vegetative ground cover will also impact on this standard. A 100% uniform colour will be the ideal, but a parameter of a minimum of 70% or greater might still be quite acceptable.

The possibility of stating the shade of colour might also be considered for different periods of the year as this may also encourage best use of irrigation, without artificially trying to green the sward when conditions are not conducive to maximum greenness.

Striping of greens, tees and fairways by mowing or brushing can significantly improve the appearance of a surface even when uniformity of colour is not as good as it should be. Surface colour is really a subcategory of the Appearance standard.

20) Appearance due to cleanness of cut: This standard is used to indicate how well the mower blades have been set and if the mower blades are sharp, slightly worn or worn/blunt.

A clean sharp cut is to be aimed for at all times, with the cleanest cuts being achieved through the use of a well maintained and set cylinder mower.

A 100% appearance from cleanness of cut should be achievable at all times because correct pre-start checks, and post-use cleaning, should ensure mower blades are suitable at all times throughout the year.

A poorly set mower will result in bruised and jagged ends to grass blades, making them more susceptible to disease.

21) Surface debris: Ideally the greens, tees and fairways will be free of any surface debris throughout the year. However, there will be times, especially during the autumn when the presence of soft debris, in particular fallen leaves, might be acceptable on a minor basis (possibly no more than 2% on tees and 5% on fairways), for up to a defined period of time (for example, being present for no greater than 2 consecutive days).

Hard debris, such as bottles, cans, medium or large stones tree branches, etc. would not be acceptable and these would need to be removed as soon as practicable.