FLOODS
Cleaning up
AGCSATech senior agronomist Bruce Macphee looks at some of the key agronomic considerations following flood events.
R
ecent months have seen some dramatic footage of the widespread rains and resultant floods impacting communities along Australia’s eastern seaboard. Many golf courses, sporting grounds, racetracks and turf farms have been inundated by flood waters, with some having only just recovered from previous flooding over the past 12 months. Such facilities will be experiencing varying degrees of damage and this article is designed to provide a summary of potential problems likely to be faced and solutions which may assist turf managers getting their facilities back into play with minimal long-term issues.
SPORTSFIELDS As with all sports turf facilities, there is no ‘one size fits all’ solution. Each venue will have to be treated individually and the solutions will be wide and varied dependent on the level of damage, period of inundation and silt deposits left behind. There are many issues which can affect how long a turf surface may sit prior to getting some much-needed attention. Access to power, clean water and equipment may limit what can be achieved when flood waters subside. 26
As with all disasters, assessing the level of damage and coming up with a recovery program is a priority. Where there has been minimal flooding, a simple verti-drain to assist with the movement of water and the re-introduction of oxygen into the profile may be all that is required. Sportsfields which have been flooded and where large deposits of silt and debris are left behind will take significantly more effort to return the surface to pre-flood conditions. Removal of silt and debris deposits smothering turf should be a priority. Turf facilities with a sand-based profile have the potential to be greatly affected with a layer of silt building up within the turf canopy, effectively sealing off the surface. Longterm there will be issues with infiltration and aeration, ultimately leading to a poor-quality surface unless action is taken to remove or limit the effects of the silt layer. Where possible, as much of the silt layer should be physically removed as possible. On a large-scale sportsfield there are fewer options for removal of silt from the canopy such as blasting with water, which can be highly effective on a smaller scale such as a golf green. Dislodging the silt and either blowing, vacuuming or brushing out of the
AUSTRALIAN TURFGRASS MANAGEMENT 24.2
canopy will be the preferred options. Each venue may have a preferred option which is effective in their circumstances. It may be a case of try it and see with the equipment you have at your disposal or utilising external equipment and labour to assist. The key areas to address first should be the high traffic areas such as goals and centre corridors followed by outfields where time may not allow an intense clean up to occur. The following options could be tried on a large scale clean up: l Removal of bulk silt and debris using a posi-track or front-end loader. l Power broom or asphalt road sweeper to brush debris out of the canopy. l If the surface has dried, a vacuum or tow behind blower may be effective at moving silt out of the canopy. l Scarifying or a light rake may loosen the dry silt allowing it to be blown or brushed from the surface. l Additional hollow coring with large diameter tines (5/8”) and removal of the cores will be required to physically break up the layers on the surface. l Topdressing with sand matching that of the profile and back filling holes will assist with improving infiltration and aeration.