“So, you just cut the grass, don’t you?” If I had £1 or €1 for every time I heard this question I would be a very rich man. The word of David Roberts ex Head of Grounds at Southampton and Liverpool and now heads up bespoke training under the name of Training Unlimited.
The pitch condition used to be the talking point before most games and also after a lot of them as the quality changed from club to club and depending on the time of year and sometimes from the start of the game to the end of it!
Manager’s and players would often place the blame of a poor performance or defeat on the pitch conditions.
Now they are very consistent with barely a blemish; it’s almost accepted that the pitch will be perfect and rarely gets a mention, and so how the pitch is managed doesn’t get thought about.
So, what is under the players feet and what does the ground staff manage?
It’s a living stage that the players perform on and a lot has changed over the years to make that stage better.
Players and coaches demand fast, consistent surfaces that the ball can travel quickly on without a bobble and the players can twist and turn with minimal risk of injury.
The evolution of sports pitches has gone through a transformation over the past few decades.
It’s hard to compare the modern pitch with the old pitches back in the 1970-80’s
So, what happened?
Many changes have occurred to give us the near pristine surfaces you see today.
- The ground staff who manage the surfaces have more resources, and a greater understanding of how to get the best out of the surfaces.
- The technology available has improved dramatically.
- The evolution of the construction of the pitch has played a huge part in the changes we see from back then to now.
Typically, we respond to problems, getting the game on is paramount. In the UK rain is the biggest problem closely followed by frost and snow.
Pitch construction changed dramatically when we went away from natural soils and onto engineered rootzones, these are specific sands chosen for particle size, particle shape and uniformity. Pitches are built with about 300mm deep rootzone, over the top of existing drainage or gravel raft, or plastic drainage raft. The gravel raft acts as a big drain but also holds water in the rootzones. Called a perched water table the sand acts like a sponge and has a holding capacity. Once the capacity is reached it drains into the gravel and goes to the drains. When the water table is full, one drop of rain falls on the surface and one drop of water drains into the gravel.
When it comes to cold, undersoil heating provided by hot water is generally the best system to keep the soil warm, prevent frost and help melt snow. This has to be managed carefully by the grounds staff as just running it at full blast will cook the grass and cause more problems! It’s an 8000m2 radiator so energy costs can be high through the frosty weather. There is approx. 20miles of pipe installed into the pitch to deliver the heat. This is placed at the same level as the gravel as if it’s installed higher it can damage the roots and be damaged by aeration equipment used to manage the hardness of the pitches.
It’s not just the drainage though! Careful management throughout the season is important. Grass grows and dies. As it continues to grow it produces roots and leaves that will die as new roots and leaves are produced. These parts of the plant will remain on the surface and in the rootzone clogging up pores in the sand. Managing the organic build up is crucial along with keeping the pores open. The ground staff will manage organic accumulation by brushing, raking, scarifying and verticutting. This can be aggressive so has to be done when plant growth is active or damage can be done to the pitch.
Renovations and Fibres
End of season is important as it’s a re-start. Full removal of the grass is the normal, replacing the top few millimetres with fresh sand to ensure that the next season the drainage rates are as good as they can be to get through the next winter. This adds a challenge as the grass is grown from seed in a very short close season sometimes with less than 6 weeks from end of season and corporate activities, concerts that take place after the season has finished.
Reinforcement systems. Sand based pitches revolutionised the playing surfaces with hardly any fixture cancelations. However, they rely on grass cover to hold them together. Once the grass was gone the pitches became unstable. Many different solutions to stabilise the surface were tried and probably the most successful has been the stitched hybrid pitch.
This is a technique that uses plastic fibres that are punched 200mm deep into the sand leaving 20mm above the surface and each stich is 20mm apart from its neighbour. It leaves a surface that is about 97% natural and 3% plastic.
It changed the feel of the pitches, they are firmer, older players don’t like them as they feel every jarring footstep. However, they are less prone to divots and far more consistent all year round. They have made a massive change to the game.
Having a plastic reinforced pitch still didn’t prevent the grass from being worn away and bare patches developing. The use of supplemental lighting has now helped grass being grown all year round. It can help create a spring-like day in the middle of winter where the lights are being used.
Evolution in the Grass Plant
The grass plant has evolved over millions of years to grow in an open environment, like the prairies in the USA, the Russian Steppes and the savannahs in Africa. We took this plant and stuck it in a stadium with little natural light and poor air flow. Using the grow lights in-between games has made a big difference with producing consistency all year round. Some stadiums, like Tottenham have integrated these lights into their infrastructure so can be quickly and easily deployed to maximise the benefits.
Sand based pitches in the UK generally use perennial Ryegrass. This species is quick to grow and very hard wearing. It has been selectively bred so that cultivars that tolerate football wear and have a good density are chosen. It can take grass breeders up to 15 years from finding a good variety to being able to produce enough seed to be sold commercially so it’s a slow process to get the next cultivar to match the current demands of stadia and the sport that’s being played.
Perennial ryegrass is a hungry grass, sand rootzones don’t hold nutrients very well so careful management of the plant nutrition is important for plant health. Amendments can be mixed into root zones to help retain nutrients and keep the plant healthy for longer. Regular testing of soils and grass leaf tissue help make sure the grass is in optimum health and only the nutrients that are required are applied.
To ensure pitches are in the best condition for play testing of the surface happens regularly. Mowing heights are regulated along with mowing patterns to make the pitch feel the same for Premier League and UEFA competitions.
Testing and Application
Pitches can be tested for hardness, traction, energy restitution, shock absorbency, stud penetration and vertical deformation along with health of the grass, moisture content, salinity of soil, nutrient content and infiltration rates. Sports medical teams can use this information to be better informed on the risks to players based on the data the grounds team can provide.
From the outside, a grounds person can be seen to be the person who cuts the grass and puts the white lines down, however as you can see there’s a lot more to preparing and maintaining an elite venue. Many coaches will tell you that in sport it’s all about the 1% here and 2% there that make the difference to success or failure. The pitch condition plays a big part in the performance of the teams.
The value of the ground staff, training and experience are more and more paramount to be able to give out elite athletes the stages they require to perform and reach their and their teams potential. David RobertsTweet
The pitch in some way is very similar to an elite athlete, its diet is managed, its rest and recovery is managed, the best most suitable cultivars are chosen to perform. It’s grown and nurtured to be at its best, ready for every match.
It’s not over yet!
The world we live in is changing, many active ingredients are being removed from the arsenal the ground staff used to use to control pests and diseases, rightly so as some of these products can find their way into water courses. It’s more important than ever that the grounds staff are prepared to manage the surface more holistically. Managing the environment to reduce stress that the turf is under is more important than reaching for the bottle of chemicals.
Pests such as nematodes, a microscopic worm that feeds on the rye grass roots are very difficult to control, climate change has seen diseases such as brown patch and grey leaf spot becoming a problem in the UK where some venues would never have seen these before.
Climate change has also meant more extreme weather events, it’s been drier, hotter, colder and wetter, every year seems to have another weather record smashed and the grounds staff have to grow grass and get games on in this more challenging environment.
Sustainability and carbon reduction are becoming important aspects of our lives in many different aspects and managing pitches doesn’t escape this. Use of power, water and fertiliser is under more scrutiny, ways to recycle, reduce and reuse are in the forefront of all decisions made on managing sports turf and trying to find the right balance between quality of the grass and quantity of products being used.
And so back to the question I got asked at the start. “So, you just cut the grass, don’t you?” The simple reply is “it’s a bit more than that!” Hopefully this article gives some insight into what the ground staff do at a Stadium. There are training centres for first team, academies and women’s teams that are being managed similarly every day.
I should ask now “Could you manage the turf at Wembley, Twickenham, Wimbledon or Lords?”
The value of the ground staff, training and experience are more and more paramount to be able to give out elite athletes the stages they require to perform and reach their and their teams potential.
David Roberts on behalf of Training Unlimited