Sports venues increasingly control the irrigation of their fields, as is the case with the lawn probes at the Zarzuela racetrack in Madrid.
Structure of the Zarzuela Hippodrome
As we can see in the diagram, there are two sand tracks and one grass track, which is the one we have to keep in perfect condition, so that the races can run normally.
In the areas most used by the public, the grass is artificial and is watered only to lower its temperature and to clean it.
Lawn at the racetrack
THE type of grass that best adapts to a racetrack is Arandinácea and Lolium fescue, with irrigation controlled by humidity and conductivity sensors.
The best for the irrigation is rainwater, which reaches all plants in a balanced way, but we do not always have this form of irrigation. Therefore we must resort to controlled irrigation, by sprinkler or drip, better underground.
At the Hippodrome we have to take into account that the force of the footsteps of the horses can tear up the grass, and this deteriorates it more when it is flooded. That is why controlling the amount of humidity is essential.
We must also take into account the salinity and pH of the water, which directly influences the absorption of nutrients.
Excessive irrigation has the effect of washing the land and eliminates nitrogen and other beneficial salts for the appearance of the field.
We can see in the diagram how the sensor measures the humidity of the wet bulb, with a depth adapted to the root system.
In the case of the racetrack, the sensors are buried, to prevent the horses from stepping on them in training and in races.
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