Layering can be partially alleviated by hollow-tining or drilling the pitch and filling the hollows with new bulli. However, the only way to fully regenerate a layered pitch is to re-lay it completely.
Most drainage problems in cricket pitches result from water penetrating under the table from the surrounding areas since water infiltrates only slowly into the bulli itself. In most situations a gravel bed under the whole table is not considered essential, but the square must be surrounded by a ring drain. This should be close enough to the surface to allow a fork to be used to get rid of surface water. The ring-drain should lead into a sump connected to a drain which will lead the water from the field. Where waterlogging is a potential problem, a firm foundation should be produced from angular 6 - 10 mm diameter gravel. Bulli/sand mixtures can be used to ease the transition from the gravel to the pure bulli.
On the pitch itself, surface runoff should be the main mechanism of getting rid of excess water. Pitches should be level between stumps but always have a crossfall of between 1 and 2% (i.e. a minimum of 3cm per pitch).
The saddleback problem arising from frequent top-dressing of the ends of the pitch (to repair bowlers foot marks etc.) must be avoided or water will concentrate at the centre of the pitch.
As mentioned earlier, topdressing material should always have similar swell/shrink characteristics to the underlying soil and it should never be spread over a layer of thatch. Also, the pitch surface, if smooth, should always be scored until rough to allow for good bonding between the topdressing and the underlying soil.
(iv) Incursion of grass from the outfield
The first control step should be taken when the pitch is first constructed. It is a wise precaution to insert, all round the wicket area, a perimeter barrier such as plastic sheeting to a depth of 25cm. While it is easiest to install this barrier at the time of pitch construction, it can be done at any stage.
A second valuable precautionary measure is to have a perimeter buffer, 1m wide, around the pitch. This area should be planted to the same grass as that used for the pitch istelf. Outfield grasses can be readily controlled in such a buffer zone before they invade the actual pitch.
(v) Bare patches on the pitch
The appearance of bare patches on the pitch is not uncommon. The areas most exposed to damage are the footmarks caused by the batsmen and bowlers. Provided these footmark areas are nursed by sweeping, lightky forking, light top-dressing, and adequate irrigation and resting, there is every chance of the under-surface stem system sending up new shoots. However, by the end of the season, footmark damage can be so serious as to necessitate replanting these areas.
A second possible cause of bare patches is localised fungal infection, leaving areas where the grass has either been killed or is badly discoloured. If there is no revival after 2-3 weeks, such patches will require replanting or patching with grass sods, provided identical bulli sods are available.
Also possible is damage by fertiliser burn. This may occur if there are slightly hollow areas on the pitch surface into which fertiliser, applied to the pitch surface, is concentrated during irrigation. Replanting may then be necessary, paying particular attention to building up all hollows with top-dressing.
In wet weather, the Umpires should ensure that the holes made by bowlers and batsmen are cleaned out and dried whenever necessary to facilitate play. In matches of two or more days duration, the Umpires should allow, if necessary, the returfing of footholes made by the bowlers in their delivery stride, or the use of quick-setting fillings for the same purpose. The 'underpinning' method is recommended for this. Grass clippings may also be used to temporarily solve the problem.
Phosphorus, potash, calcium, magnesium and sulphur should be applied according to soil test (note that there should always be less magnesium than calcium in the bulli and that superphosphate should be not be applied too liberally because the sulphur it contains will promote crumbling).
Nitrogen is applied according to demand. It should be applied regularly through the season - the smaller and more often the dressings are applied, the better. Nitrogen stimulates growth, darkens the green colour of the grass and promotes succulence. As a general rule, no more that about 6 g N/m2/month should be applied and around 3 to 4 g/m2/month should be sufficient (this translates to 15 to 20 g Ammonium sulphate or 11 to 14 g LAN). If too much is applied, the grass will become too soft and will wear poorly.
Nitrogen is generally applied as LAN, but Ammonium sulphate can be applied if sulphur is in short supply. A slow release form of nitrogen fertiliser can be useful in that it provides the grass with a more regular supply of nitrogen.
If the pH level is above 7, uptake of micronurtrients (Copper, Manganese, Zinc, Boron and Molybdenum) will be inhibited. To reduce the pH of bulli is almost impossible, so in these circumstances, one should rather make use of foliar feeds such as Supafeed to provide the necessary nutrients and to spray it directly onto the turf with a knapsack sprayer at least twice in the season.
Note:
(i) Phosphorus promotes root growth. It normally needs to be applied only once a year, in early spring. Where wintergrass in a potential problem, it should not be applied in the autumn as application at this time will promote the growth of this weed.
(ii) Potash promotes hardiness and so is important for increasing the 'wearability' of the turf. It should be applied regularly through the season (perhaps in three applications - early spring, mid-summer and in autumn, remembering that excessive levels of potash will reduce the strength of the bulli).
(iii) nitrogen promotes growth and succulence. Excessive amounts decrease the tolerance of the grass to wear and disease, and if applied too late in the summer and autumn can increase wintergrass problems where this weed is a potential problem.
It is important to note that the proper way to manage fertilising is to have the soil analysed each year. The analyses should then be interpreted and an appropriate fertiliser programme, based on these analyses, worked out.
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