For many years, the received wisdom in thoroughbred racing was that North American horses ran on dirt, while European horses were the turf experts – but it’s not quite so straightforward. After the Second World War, many European stallions who had run solely on turf were imported to the US, where they sired dirt superstars – and American-bred stallions like Sadler’s Wells have, in turn, produced top-class European grass runners.
More often than not, however, racehorses stick to the surface on which they are bred to perform best – and in the past, that meant grass or dirt; things are a little more complicated nowadays. And some horses excel on any surface – Secretariat’s final race (a victory, naturally) was over the turf course at Woodbine, John Henry won on both grass and dirt, and more recently, horses like Einstein have proven that sometimes, you just need a good horse – regardless of what the track is made of.
Modern racetrack surfaces fall into three categories:
Dirt racing is the ‘traditional’ North American racing surface, and while there are certainly major turf races throughout the US and Canada, many of the most well-known races, including the Triple Crown series, are run on dirt tracks. But each track is different, and there is some not inconsiderable variation among dirt surfaces – some have more sand, some are harder, some are deeper and some drain more quickly than others. While in general a horse bred to run on dirt, as most US-based horses are, can run well over any dirt track, some have clear preferences for particular surfaces – and are tagged as ‘horses for courses’ – although that title can apply to any surface. Dirt racing is also prominent in Japan, where descendants of Kentucky Derby and Preakness winner Sunday Silence continue to thrive on his preferred surface.
Horse racing’s history revolves around racing on grass, or turf – the thoroughbred was developed in England in the seventeenth and eighteenth centuries to compete on this surface, and they continue to do so today around the world. England’s Epsom Derby, France’s Prix de l’Arc de Triomphe and Australia’s Melbourne Cup are all run over grass, but there are many important American turf races as well, beyond the Breeders’ Cup Mile and Turf. As more top-class European horses are bred to run on grass (at least compared to their North American counterparts), major turf races in the US tend to draw very international fields – Chicago’s Arlington Million is a prime example. Most major US tracks have a turf course in addition to their primary dirt or synthetic surface; an exception to this rule is Colonial Downs in Virginia, which has a turf course augmented by a dirt track that is primarily used for harness racing – at that facility, the thoroughbreds stick to grass.
Synthetic or ‘all-weather’ track surfaces have long been used in Europe for training purposes, although there are also a number of tracks there that use them for racing as well. Designed to look and perform like dirt tracks (broadly speaking), they are typically comprised of some combination of rubber, wax, synthetic fibers and sand. As with dirt racing, no two synthetic surfaces are identical – in fact, there are a number of competing products that yield rather different results. Santa Anita’s controversial Pro-Ride surface has not lived up to its ‘all-weather’ billing, with many cards canceled for rain, but the same surface has proven effective across Australia, where it was developed. It is the track’s second attempt at a synthetic surface – the first, utilizing the Cushion Track product, had continual problems, although it is still used at Hollywood Park. Another synthetic surface, Polytrack, is used at major tracks such as Keeneland, Del Mar and Woodbine – it is also the primary synthetic product used in Europe. Another option, Tapeta, has been installed at Meydan, where the Dubai World Cup is contested; prior to 2010, the race was held over a traditional dirt surface.
While the switch to synthetic surfaces was driven by a desire to reduce injuries for both jockeys and horses, results have been mixed – with such variation among surfaces (both dirt and synthetic), a true one-to-one comparison is difficult. So far, the data does not support the position that a ‘good’ dirt surface is any more dangerous than a ‘good’ synthetic surface – but the jury is still out. The one generally-agreed upon notion about synthetic tracks is that they are favorable to grass horses; while it is true that races over synthetic often play out more like turf races (fewer runaway winners, more blanket finishes), it cannot be claimed that every good turf horse will easily win on a synthetic surface – nor that the chances of a good dirt horse are somehow entirely compromised. Some horses clearly relish synthetic surfaces over all others, but it’s a bit too early to predict whether stud farms will begin to promote their stallions as begettors of great synthetic stars.