In the maintenance of a cricket outfield, success or failure of such work is influenced by whether the area is to be used solely for cricket or for any winter sports.
The ideal cricket outfield should be firm, fast and true, and present no hazards to any player as a result of a ball bobbling up from an uneven surface. Ideally, from a cricketer's point of view, hockey would be a preferred winter sport as it tends to be less stressful on the grasses and ground conditions. Alas though, hockey is now established as a game played on artificial surfaces, and long gone are the grass pitches we knew in the past except, perhaps, at independent schools. However, if football or rugby is the preferred sport, then a different strategy has to be employed.
In the past, old and ancient cricket clubs possessed poor levels of outfields, a feature for some clubs, but also as a result of having originally being constructed from existing ridged and furrowed land or land left fallow where heavy clay is the predominant factor.
Where this problem is severe, i.e. where the topography is very undulating, it can lead to varying depths of topsoil existing over high and low spots which, in turn, will affect grass coverage and create wet and dry hot spots. The only way that this problem can be overcome is to carry out large scale regrading and levelling. This can be very costly and involves regrading sub soils and the levelling of topsoil. Where the undulations are not too severe, and there is a good depth of topsoil, then it is more practicable to remove the topsoil, grade the subsoil to the required levels and replace, or introduce new topsoils compatible to the ground conditions. Where isolated undulations occur, much smaller scale work could be undertaken to overcome the problem.
The installation of a pipe and slit drainage system would also be beneficial, as this will remove excess water from the site, although this type of work should only be undertaken by an approved contractor.
Where the outfield has a reasonably level surface, but is used for more vigorous, heavy duty sports, such as rugby or football, then the maintenance of it becomes more involved. The area needs to be sustainable for the duration of its season and contain good grass coverage, be weed free and possess good drainage.
To have good grass coverage, a sward composition favouring a mixture of high quality perennial rye grasses (Lolium perenne) would be the preferred choice, as the close season for football can be relatively short and, with moisture levels very low, it is crucial to select cultivars that will give you rapid establishment, exhibit wear tolerance that is required by such sports and require little or low fertility; but also show resistant to disease.
For outfields that are solely for cricket, then a sward composed of fine turf cultivars such as Chewings fescue (Festuca rubra commutata), Slender creeping red fescue (Festuca rubra ssp. litoralis) and Brown top bents (Agrostis tenuis) are more desired, as these species are more tolerant to drought, fast germinating and can be mown as short as 7-10mm, providing a faster, smoother surface.
When swards are dominated by fine leafed fescues and bent grasses, the need for fertilisation is greatly reduced as these grasses thrive in low fertility conditions. Furthermore, a faster growth rate would require more frequent mowing and adds to the maintenance costs. To be exact on the fertility rates can be extremely difficult, as this depends on the inherent fertility of the soils and intensity of wear and tear.
Of the three main plant nutrients for fine turf, N, P and K, nitrogen is the most important, since it is the element that is primarily responsible for encouraging the growth of stem and leaf. Phosphate, however, affects all plant growth processes and is particularly involved in root development, whilst potash, which rarely produces obvious benefits in turf, is linked with the general health of the plant. Its function is to encourage resistance to disease, drought and to severe winter weather, particularly when there is a high level of nitrogen in the soil.
Apart from N, P and K, iron is one minor element of definite value, when included in fertiliser programmes for most kinds of fine turf, since it helps give the grass a good dark green colour and reduces weeds, worms and disease. Sulphate of iron is widely known for its darkening effects on turf colour, producing a more attractive sward as well as a traditional treatment for the control of moss. The greening effect is mainly due to the darkening of dead material at the base of the sward which makes thin or bare areas less noticeable.
Fertilisers, when regularly used on fine turf, should be slightly acidic or neutral in their effects. Where possible, avoid alkaline materials as this will influence the botanical composition of the grasses encouraging weeds and worm activity.
It is most important to know the fertility of your soil before applying any type of fertiliser treatments. You should have your soils tested regularly to determine the pH to ensure the acidity levels are correct. Soil pH may vary from area to area in which you intend to plant or amend. Therefore, it is important that you take a number of samples for analysis. pH is measured from 1-14, 1 being the most acidic, 14 the most alkaline. Most plants have a reasonable wide tolerance of at least 1pH point and will be comfortable with a pH of around 6.5.
pH can contribute to the build up of fibre, with acidic conditions favouring an increasingly fibrous surface. After having a soil analysis taken of the outfield, and if results show a high rate of acidity (less than 5.0), then careful adjustments need to be made to increase the alkalinity via your fertilising programmes. Annual applications of ground limestone (carbonate of lime) could be considered in the early autumn or winter, allowing it to be washed into the soil following a programme of aeration.
To increase soil alkalinities annually, add ground limestone as indicated by the table.
Mowing of outfields should be carried out throughout the growing season, two to three times a week if playing a high standard, and more frequently for first class matches. In an ideal situation, the use of a ride on triple cylinder box mower, with a cut width of 72" and all resulting clipping being boxed off, will help maintain a fast smooth surface and aid presentation. The mower (or cylinder) should be set between 10-15mm. Resist scalping as this, in turn, can create stress on the grasses and encourage disease.
Where time is of the essence, then the use of a tractor mounted set of hydraulic or trailed gangs would be very beneficial. These have a distinct advantage as the clippings generated by this operation are returned back to the turf. Any loss of nutrients is limited as everything is recycled, resulting in less fertiliser being applied. The only downside to this operation is the trailed or mounted gangs do not have the capacity to firm the surface, as a ride on or box mower would have, and the tractor wheel markings would be more noticeable during times of inclement weather.
Mowing should be carried out at regular intervals, with the frequency being reduced during the winter months and only carried out during active growth.
Where the outfield is adopted for a dual use purpose, i.e. rugby or football, then the mowing regimes and the type of machinery required would have to be tailored to the resulting sport. Tractor mounted rotary mowers can produce a good even surface for winter sport as well consolidating the surface for the ball to run smoothly. The height of cut will vary between 25-35mm for football and 50-75mm for rugby.
However, during the early spring and summer months, these heights can lead to problems with mowing; the need to reduce to cricket heights should be resisted, as this will also put stress on the grasses. The heights should be reduced gradually at 5mm or no more than 2/3rds of the grass plant at a time. This will strengthen the sward and create more density to help with wear and tear.
When regular maintenance is not carried out, then a cricket outfield can quickly become soft and spongy, as a layer of fibrous organic material develops at the base of the sward. This problem is most particular where fine leafed grasses dominate and where regular aeration has been neglected. Scarification and aeration of the outfield is vitally important to reduce the effect of thatch build up. Scarifying at the start of the cricket season will prove highly beneficial in combating thatch. This operation, by linear aeration, will physically rip out and remove any straggly stoloniferois and procumbent growth. By regular scarifying, verti-cutting, harrowing or raking, at least once a month, will help keep the surface open and dry. It will also reduce the accumulation of organic matter, allowing much needed air and nutrients to the roots.
Thatch, the accumulation of a layer of fibrous material, is a natural feature of turf development and cannot be entirely prevented. Total prevention would, in fact, be most undesirable as surfaces with no underlying fibre would lack resiliency and would easily become muddy in wet conditions. However, when fibre builds up to an excessive degree it becomes a problem. A few millimetres of thatch in most cricket outfields is acceptable, whilst a layer of 25mm or more would become troublesome.
Thatch is water retentive throughout most of the year and smells strongly of decay and stagnation. It is yellow/brown in colour with black streaks showing the activity of the anaerobic bacteria. The underlying soil is wet or saturated, compacted and usually on clay with restricted drainage. Organic matter accumulation may, therefore, be caused by excessive production or insufficient decomposition of grass clippings. In the case of sportsturf, excessive fertiliser treatments increase production.
Where a thatch problem has developed, deeper scarification should be adopted. Ideally, a tractor mounted rotary unit with collecting facility should be used, as this will remove a large majority of material in a single pass. If this is not available, then a pedestrian unit can be perfectly adequate if used on the area immediately behind the cricket table. A tractor mounted rake or short toothed harrow will also suffice.
Where the problem of thatch is particularly severe, then a more drastic approach is required. The process of koroing, the removal of all vegetation and organic matter built up in the surface is an expensive and costly exercise.
A cheaper option of hollow coring is more practicable, but may take many years. This will incorporate the use of hollow tining, the physical removal of cores containing thatch. The cores should then be collected up and disposed of or recycled as compost. A dressing of medium fine sands worked into the profile will also help to break down any thatch build up at the base of the sward. This will also assist in air movement and nutrients being made available to the plants root system and promote a healthier sward.
Compaction on a cricket outfield, caused by intensive play and heavy maintenance equipment, is the biggest single problem encountered on sports pitches today. Grass roots grow in the pore spaces created between soil particles and, when these spaces are reduced by surface compaction, the roots are deprived of oxygen, water and nutrients, resulting in a weak, shallow root structure. Without strong root growth, the grass becomes weak and sparse and is prone to excessive wear and vulnerable to turf disease.
Deep seated compaction can also lead to drainage problems. If this is the case, then the only remedy is to carry out deep, solid tine aeration, penetrating to a depth of 250-400mm with 25mm tines. This will create fissure breaks in the underlying soils and allow water movement through the soil profile. Further deep aeration should follow during the winter months, with the use of slit tines, penetrating to a depth of 100-150mm, or an Imants Shockwave if ground conditions warrant. This too will improve root structure, as the grasses search for the pore spaces being made available.
On areas of fine turf, the main purpose of topdressing is to preserve a true and level surface and to dilute the build up of thatch. Ideally, an annul application of 5-6kg/m2 of topdressing, divided into several applications, is the most practical. If the playing surface is on a heavy clay soil with poor drainage, or has excess thatch larger quantities, topdressing should be applied in conjunction with a hollow tining programme, so that drainage and aeration of the surface layer can be improved.
Consistency in the use of topdressings on fine turf is important, as the use of pure sands (or straights) for one year, and reverting to a mix of sand/ soil the next, could form a root break, causing a significant effect on the vertical movement of soil moisture and the penetration of grass roots.
In areas of fine turf, the lime content of the topdressing material is critical. If the sand contains large quantities of shells or calcareous material then the pH of the surface layer will increase. This could have an affects on weeds, earthworm activity, turf grass disease and the composition of the grass species within the turf, in particular the invasion of annual meadow grass (Poa annua), at the expense of fescues and bent species.
Other main concerns, where the outfield has dual usage, is the renovation of worn areas through the short period at the end of their season, such as football goalmouths, touch lines and centre circles.
In the case of rugby, bare areas caused by scrimmaging, the work required here would be to harrow or rake over the worn and bare areas to reinstate the levels and create a seed bed. Aerate the area with solid tines to a depth of 100-150mm to decompact. Overseed the area with a suitable perennial ryegrass and, where possible, topdress to cover the seed. A pre-seed fertiliser may be required in the event of larger areas of recovery.
Irrigate as required to establish early germination to prevent the area being taken over by weeds. Where worm casting, moss colonisation or an attack of disease, such as Fusarium (Microducium nival) becomes noticeable, an appropriate control for fungicide should be adopted with a person holding the necessary qualification certification.
Remember, your outfield will have a major effect on a game if unattended. The outfield should be treated the same as any other natural grass pitch, carrying out regular mowing, verticutting, aerating, topdressing and feeding programmes to maintain a level surface, healthy sward and a sustainable playing environment.