Bowling Green Maintenance: 04e. Performance Standards

12) Surface evenness: The smoother the surface the better the consistency of play. Unevenness and depressions can be readily identified by using a 3-m straight edge: a variation of no more than ±12mm might be considered acceptable for many greens, but for high quality greens this variation might be reduced to ±6mm. Where animal damage occurs, such as from rabbit scrapings, fox holes or bird peckings then these would need to be immediately repaired and evened out. For greater distances a string can be put down and pulled taught to provide a measure of the extent of depressions present within a green and this is something which might not be adequately identified by using just a much smaller 3-metre straight edge. Running a string form one end of a green to another and identifying low spots can be really helpful, at renovation time so that additional top-dressing can be applied in the worst depressed areas.

13) Infiltration rate: the removal of water from the surface increases the likelihood of a game being played. High sand specification greens will typically have a minimum rate of 100-150mm per hour, although in practice this might be higher for a newly constructed green. However, for a summer sport this is arguably an over specification for greens in the UK. Sandy soil-based greens might aim for a minimum of 25mm per hour, whilst general quality greens a figure of no less than 12mm per hour might be acceptable. The rate of percolation is also important because whilst the initial infiltration into the surface might be satisfactory, if the rootzone has a compaction layer in the soil profile then the water won’t be transmitted very far and gradually the soil pores will fill up with water resulting in a waterlogged green, and this will be particularly problematic where an undesirable thickness of thatch is also present.

14) Fine particles (i.e. <0.125mm): There is little that can be done with an existing soil texture in practice, unless excessive cost is to be incurred. So, whilst parameters might be given any weighting used for an overall quality assessment might be low as this is outside the control of a ground’s manager. However, most greens have been constructed with a relatively free-draining sandy material, but this can still contain a relatively high percentage of fines. For an existing and established green a figure of no more than 30% fines might be desired, especially considering that a sandy loam in the UK Soil Textural Triangle will contain from 50% to 70% sand, and 30% to 50% silt and clay. For a high specification sand based or sand dominated green this might be a maximum of 10%.