The key to good pitch preparation is moisture content – and it has a direct impact on performance. Basically, water held within the pore spaces of the soil (loam) helps to bind the particles together, acting like a glue.
Under-prepared wickets have too much water; the clay loam hasn’t had chance to dry and be compacted by the roller. The ball therefore creates an impression in the surface which then leads to the ball changing direction or ‘seaming’.
On the other hand, an over-prepared pitch generally becomes slow and low as it dries. This is because the moisture which was once held within the loam is removed by evaporation or the grass plant.
In between the two is the optimum moisture level for energy to be returned back to the ball and maximum pace obtained for that pitch.
It’s important to note that there is no black and white instruction manual when it comes to pitch preparation. The art and skill of a cricket groundsman is to judge their own individual pitches and to time the start of play in the moisture window ‘sweet spot’.
Most cricket tables have an historic profile, which means that they have been built up over many years by top dressing. These profile types exaggerate the drying effect because the layers also separate and allow the energy of the ball to dissipate.
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