As punters ready their wallets for a flutter on the Grand National, STRI agronomist Richard Wing takes a look at what goes into producing a fair and safe racecourse.
National Hunt requirements
The BHA have their mandatory requirements and targets for the courses through the National Hunt season but clearly weather conditions can reduce the ability to influence the performance from time to time.
Jumps courses should aim to provide ‘good’ ground and definitely no firmer than ‘good to firm’. These targets are set to ensure reasonable horse and jockey safety when racing by providing a good level of grip in the take-off phase and correct impact firmness and cushioning on the landing phase.
What is ‘good’ ground? The classification of ground on a racecourse is given by a combination of a measurement using a TurfTrax Going Stick and a visual assessment from the Clerk of the Course. The tendency is to provide a softer ground to ensure reasonably horse and jockey safety and moderate times.
Adjusting the Going
Maintenance of a racecourse is constantly tailored to achieving the target of ‘good’ ground come race-day. The key to producing a fair and safe racing ground is good interaction between the soil and the grass. The reduction in quality or health of either will impact on the surface performance.
With the vast expanse of land that a racecourse covers it is inevitable that soil types and structures vary across the course. The aim is to produce good soil structure through the upper profile with the soils becoming tighter lower down without excessive firmness.
Tailoring maintenance practices to the soil types is vital to creating uniformity through a varied aeration programme, suitable nutrition and proficient moisture management.
Organic matter naturally accumulates in turf and provides cushioning and some wear resistance, but excessive amounts leads to surface softening and an increase in disease pressure.
Mechanical removal through scarification and maintaining an aerobic soil with aeration aid to maintain the required level.
In general, the more aeration carried out the better, but the effectiveness of the operation can be maximised by selecting the correct method and timing.
Aeration variations are very much soil specific and should be carried out to target the specific issues in the profile. More importantly is the timing of the operation.
It is important to note that the timing of aeration is important, and the soil structure of the course and the potential recovery should be considered before carrying out the operation.
Verti-draining is effective in relieving compaction through the upper profile but carrying out the operation when the soils are saturated can have a detrimental effect causing additional sealing and compaction.
Maintenance should be tailored to promote a ryegrass dominant sward to provide a high wear tolerance, good footing and support, accelerated recovery and a dense sward at the target height of cut.
Every opportunity to improve the sward composition should be taken by including ryegrass seed when forcing recovery from wear.
The BHA set their height of cut guidelines at 4-6-inches to provide grip and reduce hoof slides, good wear tolerance and to encourage deeper rooting.
Nutrition levels should be tailored to the soil type to provide adequate fertility to promote a healthy, dense sward with goof turf vigour. Excessive nitrogen levels will cause ‘soft’ growth which can cause the turf to become slippery and reduce grip.
Proficient moisture management and aeration will encourage deeper rooting of the sward improving the impact firmness and responsiveness of the surface during racing.
Excessive or insufficient moisture in the profile can cause issues for horse safety and a close monitor or rainfall and irrigation is part of the BHA mandate prior to racing.
Harrowing and scarifying
Scarification and harrowing of the surface have benefits to racing by reducing grass nap along with the physical removal of organic accumulation.
Grass nap compromises the grip of a racing surface creating a slip hazard for the horse. Reducing this through scarification is a crucial operation prior to racing.
The operation does require a recovery period and should be planned to suit the racing calendar.
It is extremely difficult to provide the perfect equestrian surface as the weather conditions of the year have their impact on the soils and turf health.
However, with a good management strategy combining appropriate aeration, fertility, irrigation and other cultural practices to suit the individual racecourse this can be strived towards.
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