Suggestions for a correctly constructed pitch
(a) Carefully assess the drainage requirements. Unless there is a danger of a perched water table developing, a perimeter drain surrounding the table should be sufficient to drain surface water and reduce lateral uptake of water by the table if a plastic lining is not present.
(b) Avoid elaborate (and unnecessary) combinations of a range of materials under the bulli. Medium crusher-run stone should be sufficient.
(c) Ensure that only good quality clay which has been analysed and passed as suitable is used.
(d) Consult widely and make certain that each stage of construction has been carefully researched and planned. Do not allow a hurried operation to justify short cuts.
(e) Be absolutely sure that adequate compaction occurs at every possible stage.
Summary: Recommended procedures for constructing tables vary considerably. Consult local Cricket Union groundsmen and follow proven specifications for your area.
A few examples are given here of recommendations which have been published (our additions are in italics).
Construction specifications will refer to the following factors:
(a) Base conditions and base layers. The general specification is medium crusher run stone.
(b) Each layer of material must be bonded or keyed into the layer below.
(c) The quality of clay must meet standard specifications. Refer to your Union groundsman before deciding to purchase bulli.
(d) Good compaction must be achieved at each level and sub-level.
(e) Ten examples of pitch construction revealed that, on average, the total depth of excavation was some 450mm, of which the clay soil depth was 240 - 250mm (54%). Our information suggests that senior games lasting four or five days demand greater depth of clay for adequate preparation and strength. Shallow bulli must be avoided.
(f) Less than 100mm bulli is not recommended. Bulli of this depth should be compacted onto a stone layer and not onto loam or sand.
(g) Insert plastic sheeting between the table and the outfield to prevent encroachment of invader grass species.
Example No 1.
(i) Excavate table to 280 mm.
(ii) Lay strips of plastic down the edges of the excavation to prevent grass from entering the pitch area from the surrounds.
(iii) Add crushed stone to a depth of 150 mm. Compact the stone and then score the surface.
(iv) Apply 40 mm fine to medium gravel. Wet and compact. Score the surface.
(v) Complete filling with 90 mm of bulli, firming the material while filling. (Fertiliser, and particularly phosphate, could be mixed in with the bulli at filling to promote root growth. The amount needed can be determined from analysis).
(vi) If necessary, apply potash on the surface.
(vii) Plant sprigs 40 mm apart or spread sprigs over the area after watering, cover with a thin (5 mm) layer of finely crushed bulli and roll with a light roller.
(viii) Once established, topdress to level three or four times.
(ix) Fertilise monthly, irrigating the fertiliser in. Apply, in alternate months, 60 grams of 3.1.5 and 30 grams sulphate of ammonia per square metre.
(x) Roll in all directions - across, diagonally and in line with the pitch. Repeat this often after flooding.
(xi) Cut regularly to a height of 20 mm.
Example No. 2.
(i) Excavate to 300 mm. Slope base gently towards a sump, filled with stones, at one end. Compact base of excavation.
(ii) Line the vertical sides of the excavation with polythene/plastic.
(iii) Place 120 mm of 13 mm crushed stone into the excavation and compact. Mix in sand to assist with compaction.
(iv) Add 80 mm of a loam soil and mix in 50 g supers and 50 g 2.3.2 fertiliser per square metre. Level, water and compact.
(v) Add 100 mm bulli and compact.
(vi) Wash grass sods to remove all soil and tease sprigs apart. Lay sprigs on bulli surface. Add a thin layer of sieved bulli to a depth of not more than 15 mm (sieve apertures 10 mm or smaller) over the grass and smooth.
(vii) Apply 3.1.5 at 50g per square metre and water.
(viii) Water lightly twice daily with a fine nozzle spray until grass shown signs of sprouting.
(ix) Continue to water once daily until grass has covered.
(x) Apply Ammonium sulphate or 4.1.1 fertiliser (50g per square metre) monthly and water.
(xi) Once the grass is well established, topdress.
(xii) Cut to 15 mm.
(xiii) Rub in sieved (1.25 mm gauge screen) bulli, making sure that the grass tips protrude above the bulli.
(xiv) Lightly water twice daily until grass shoots push through.
(xv) Repeat (xiii) and (xiv) until the final level is reached which should be slightly above the level of the outfield.
(xvi) Roll for half an hour with a hand roller in a dry state.
(xvii) Once established, cut as short as possible and apply 3.1.5 and supers (25g/m2 of each) and flood.
(xviii) Commence normal preparation.
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