Artificial grass pitches have been built in large numbers in the past few years.
They have advantages over natural grass in several ways.
In particular, they do not degrade if the weather is too wet and will not require irrigation if too dry.
For tennis courts frequently paced patches retain the same surface characteristics throughout the season.
The advantages come at a price:
- The pitch has to be kept free from biofilm.
- Phototrophic organisms settle first.
- They need CO2 and sunlight as their carbon and energy souce.
- In artificial grass they are mainly algae and cyanobacteria.
- The biofilm evolves with the appearance of heterotrophic organisms (most bacteria and all fungi)
These organisms need some organic source for their growth, and this is provided by the metabolites of phototrophic organisms or by air-borne deposition. The biofilm community consists in nature of mixtures of bacteria fungi, algae, yeasts, protozoa, and other microorganisms settling within the infill and on the grass filaments.
The condition of the pitch is therefore directly in relation with the ability to control the biofilm.
If this is mastered, the low maintenance promise can be kept.
If not the consequences are at several levels:
- The infill undergoes caking. The surface becomes hard, unforgiving to the player.
- The drainage slows down, not always everywhere at the same rate on every part of the pitch. The biofilm begins to thrive until the drainage channels within the build- up clog up completely.
- The players skin grazing become septic at the onset.
The solution is relatively simple if minimum precautions are taken:
- The biofilm needs killing at least twice a year, sometimes more often depending on the exposure the pitch.
- Proximity of trees in particular.
The biocide of choice is Algoclear Pro:
- It is a high purity quaternary ammonium with environmental credentials.
- High purity means solvent free.
It is important to avoid interaction with the polymers the grass blades are made of, as well as the geotextile fleece sometimes used in the drainage layer.
The environmental acceptability is in the property of the chemical to degrade on contact with biomass. Any excess product will therefore breakdown as and when draining outside of the build-up into the ground, preventing chemical migration futher into the soil.
With regard to concentration and application rate, there is some flexibility.
The same dosage can be dispensed in a higher concentration, linked to a frugal application rate, or a lower concentration compensated by more copious spraying.
The water will evaporate, and the amount of dry quaternary ammonium remain on the pitch. If the objective is to salvage a caking infill, the higher application rate makes sense as the sand is treated deeper.
If the court is in good condition, the treatment being periodical maintenance, spraying of extra quantities is not justified.
The precise proportions are adapted to the type of pitch, fill depth, frequency of the treatment etc.
Contact Cropcare for detailed information.