10. OTHER EXAMPLES OF PITCH PROFILES
Note: the layers referred to here are listed from the top to the bottom of the profile.
Example No. 3
This comprised the following layers:
Layer 1: 150 to 300 mm fumigated bulli (around 60% clay), the depth increasing the longer the expected duration of the games
Layer 2: a blend of the bulli with a sandy loam
Layer 3: 150 mm fumigated sandy loam
Layer 4: drainage (gravel) if required.
Example No. 4.
Layer 1: 80 mm of bulli
Layer 2: 40 mm of a 70:30 mixture of bulli and sand
Layer 3: 40 mm of a 50:50 mixture of bulli and sand
Layer 4: 130 mm of a fine/medium sand
Layer 5: 50 mm of coarse sand
Layer 6: 120 mm of 6 to 9 mm gravel
All this is surrounded, side and bottom, with a plastic membrane.
Example No. 5
(i) 150 - 200 mm bulli
(ii) 100 mm loose sand
(iii) 100 mm coarse sand
(iv) natural soil into which drains are cut.
Example No.6 (Jack Manning):
80 mm bulli; 40 mm gravel; 100 mm crushed stone
Example No. 7 (Wanderers - old)
300 mm bulli; 150 mm crushed stone
Example No. 8 (Adelaide)
300 mm bulli; straight onto a strong base
Example No. 9 (Newlands - new)
150 mm bulli; 300 mm laterite; 300 mm dune sand
Example No. 10 (Maritzburg)
250 - 350 mm bulli; 150 mm crusher run
The need to relay a pitch is usually due to a sub-standard clay having been used initially or because the pitch has layered and is sheared horizontally, resulting in poor playing conditions. Bear in mind that both these factors are controllable, and that this state of affairs has expensive consequences considering that some 12 cubic metres of good quality bulli has to be procured and compacted into the pitch for re-establishment.
(i) Anyone planning to relay a pitch should follow the previous proposals, and consult and plan the operation to avoid preventable pitfalls.
(ii) Take into account those factors which resulted in the necessity to relay the pitch and ensure that previous mistakes are not repeated. Make certain that you are using the best quality clay possible.
(iii) If clay quality was not the problem, it is probable that the previous pitch had layered with organic matter and had sheared horizontally with habitual cracking.
(iv) Assuming that the pitch has adequate drainage and was well laid in the first place, it may be necessary to remove only the upper 150mm of bulli. The surface must be scoured and prepared to ensure proper bonding with the fresh material which is likely to have different characteristics.
(v) Ensure correct levels and reinstate barriers to prevent encroachment of invader grass species.
(vi) When establishing grass, be careful not to introduce a foreign growing medium into the pitch. Grass grown in bulli is suggested. An alternative method is to soften the final surface and rake before flooding and planting to a certified grass. Use washed grass sprigs (these can be washed with a high pressure hose to ensure that all the previous growing medium is removed). The sods are then teased apart. The washed grass sprigs are then spread on the surface, covered with sheeting and cross rolled a number of times. The sheeting can be left in place for a while (5 days) to keep the surface moist and water can be applied as necessary. Within one week the grass should have started to grow.
(vii) The whole operation should take six men about 10 hours.
Note: The pitch should not be played on during the first season to allow for good root development.
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