Behind the Forecast: The Kentucky Derby vs. Kentucky weather

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Behind the Forecast: The Kentucky Derby vs. Kentucky weather
Tractors on track Churchill Downs (Source: WAVE 3 News)

LOUISVILLE, KY (WAVE) - It’s horse-racing time and weather can place a pivotal role in the races themselves and even the revelry around the races (as we learned with the deluge on last year’s Kentucky Derby). Some that, of course, is key to all horse races (other than the horses and jockeys) is the track.

There are three different types of tracks: dirt, turf and synthetic. The conditions of dirt and turf tracks fluctuate based on weather conditions while synthetic tracks are more consistent, according to KentuckyDerby.com.

While Thoroughbreds are built to run, the weather and track conditions can certainly influence a race.

Synthetic tracks are no longer as prevalent as they were in the early 2000s. Two of the most popular types are Polytrack and Tapeta. They are made up of mostly sand, rubber and fibers which are then covered in wax. Keeneland installed Polytrack in the fall of 2004 and actually worked to help market it in the United States, the New York Times explained. However, Polytrack was removed from Keeneland in 2014.

The top layer of the track is called cushion and helps to reduce the impact on horses hooves since it is soft and granular, according to Science. The layer below, the pad, is much more rigid and compact. This gives the horse a sturdier surface to push off of.

Dirt tracks remain one of the most popular in the United States. Dirt does not always provide enough shock absorption for a horse’s hooves which is why care and composition of a track are important. At Churchill Downs, the one-mile oval track boasts a “12-inch resilient clay base on top of a 25-foot sandy loam sub-base”, their website explains. Eight inches of a sifted and mixed combination of 75% round river sand, 23% silt and 2% clay sits on top of the clay. Churchill Downs says that the top three inches act as the cushion for the horse while the 5 inches below “protects the horse from ever reaching the sturdy base.”

Signalman prepares at Churchill Downs (Source: kentuckyderby.com)
Signalman prepares at Churchill Downs (Source: kentuckyderby.com) (Source: kentuckyderby.com)

So how do you take care of one of the longest stretches of track in horse racing while dealing with the wild Kentucky weather? Crews harrow, roll, seal, grade and even water the track depending on ongoing weather conditions. A chain harrow is pulled behind a tractor, breaking up the dirt and helping to create a more even surface. Then the track is watered depending on the existing moisture content and sealed and smoothed with a float. A float is a sheet of metal or wood with weights that is dragged over a race track to help with water drainage and smoothing and compacting the surface of a race track.

The various conditions for dirt tracks in North America are as follows:

Fast Dry
Wet-Fast The track has a wet surface, but moisture has not been able to penetrate the lower layers of the track.
Good A surface that is drying out or has had recent, but not much rainfall.
Muddy A wet surface, that tends to have slower times than a good surface. Moisture has seeped towards the track base.
Sloppy A very wet track with water visible on the surface. The base is still quite solid The rain might still be coming down, or stopped; drying has not yet begun.

According to Mick Peterson of the Racing Surfaces Testing Laboratory, who actually works with Churchill Downs, stated in an interview with Science that the cushion layer of the track works best when it is 14% water. Watering the track can help to offset evaporation while sealing can help to keep water out. Even the shadows of a race track’s grandstand can impact a track, causing some areas to dry out faster or stay wetter longer than others.

(Source: WAVE 3 News)

Now off to the turf which has its own benefits and drawbacks. One advantage is that dirt and mud aren’t thrown into the faces of the horses and jockeys. However, turf can be just as impacted by the weather and use as dirt tracks. Overuse can cause a turf course to become dry so seeding and fertilizing become critical during breaks in racing.

The conditions for turf tracks in North America are as follows:

Firm There is little moisture and the surface is resilient
Good A turf course with some moisture, and softer a firm course.
Soft A course with a lot of moisture than a good course, and significant give.
Yielding A very wet turf course with ample “give”.
Heavy The wettest possible turf course; basically waterlogged

Churchill Downs has a ⅞ mile oval with a sand-base. The turf itself is comprised of 90% fescue and 10% Kentucky bluegrass. Churchill Downs site states that the inside rail is rotated regularly between lane 1 (on the hedge), lane 2 (15 feet off the hedge) and lane 3 (22 feet off the hedge). The course also has a “state-of-the-art drainage system under the turf to ensure that the course dries quickly.”

A GoingStick or penetrometer are used by tracks around the world to measure a course’s conditions. It sinks into the soil in several locations to determine the soil’s hardness and an average is taken to determine the rating.

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