Mowing Outfield In-Season

Why do we need to mow the outfield?

Regular mowing is important to provide the right length of grass for good ball roll across the outfield, to encourage good plant density and support player safety when moving and diving in the outfield.  Good presentation of the outfield can give a good first impression and enhance the enjoyment of participants and spectators.

What equipment is used?

Cricket outfields are large areas and are mowed with a variety of equipment including:

• Large pedestrian cylinder mowers (cutting width of 32”+, usually with a seat attachment for the operator).
• Ride-on self-propelled cylinder or rotary mowers such as triple golf greens/tees mowers or even 5 to 7 cutting-unit fairway mowers.
• Trailed gang mowers mounted on a tractor or other vehicle.
• Large working width rotary deck mowers driven by a tractor power take off.

The cricket outfield does not need a mower with as high a clip frequency as required for pitch preparation. 

The important characteristics are a large working width to maximise work rate, good control of height of cut (particularly across different cutting units on the machine) and the ability to follow undulations and contours where required.  Cutting width is important and equipment needs to be selected carefully to allow the outfield to be cut in the time available and for the number of times per week to maintain the desired grass height without creating piles of grass clippings at the surface.

Bear in mind that if you are using your outfield for winter sports such as football and/or rugby then you will need to consider range of height of cut and ensure that ground pressure is low using suitable turf tyres.

What is the right cut height and how frequently should I mow?

During the playing season, mowing heights on the outfield should be 10 to 20 mm. The aim is to choose a height that is manageable, promotes the health of the sward and the characteristics of the grass plant that are desirable for cricket, and of course provides a smooth ball roll during the season.

The height of cut should be a decision based on how the sward is growing (particularly in relation to soil moisture content), prevailing temperatures and hours of daylight, the time of year, the smoothness of the surface, the standard of play and the frequency of mowing.

Reducing outfield cut height can improve ball roll speed – making an outfield faster but it is not the only factor controlling ball roll (and bounce for elevated shots), others include:

• The grass species mix and the different growth patterns of different grasses.
• Weather, drainage and soil moisture content
• Surface hardness / compaction
• Surface smoothness and undulations
• Slope between the square and the boundary.
• Weed content

Lengths over 18 mm are perceived to be ‘long’ by players and may not provide good ball roll.  However you should not set your cut height at a level that scalps the outfield or damages equipment if your outfield undulates. Click here for information on repairing the Outfield.

Mowing should take place as and when needed, making sure that never more than one third of the total length of grass is removed in any mowing session.  This typically varies between one and three cuts per week during the season, depending upon cut height, growing conditions and opportunities to cut.

The number of cuts required per week will depend on the rate at which it is growing which will change in response to temperature, nutrient status and rainfall/irrigation.  Allowing the grass to grow too far between cuts will result in excessive clippings which will form into piles and can affect ball roll.  Ideally an outfield should be cut on average twice-weekly but in periods of fast growth this might require three cuts a week or only one in extended dry periods.

Grass Clipping Removal – to box or not to box?

Unlike on cricket squares, clippings from outfield mowing do not need to be collected and removed as long as there is good thatch control in place and the outfield is cut frequently to minimise the length of clippings.  Boxing-off (collecting and removing) clippings does provide the highest standards of presentation and performance and will slow the rate at which thatch accumulates.  However it slows the work rate of the mowing operation significantly (the boxes need to be emptied), it increases the quantity of grass that needs to be disposed of or composted on site and increases fertiliser demand (letting clippings fly recycles nutrients from the cut leaves back into the soil as they decompose).

Cutting the outfield frequently means that clipping length is shorter and the leaves decompose more quickly and more fully, reducing that accumulation.  As long as cut height is reduced gradually in the transition from winter into summer cutting heights, and the outfield is cut frequently so that clipping length is minimised then the majority of cricket clubs will be able to let clippings fly when cutting the outfield, rather than boxing them off.

Presentation

The highest standards of presentation can be achieved by creating stripes with the mower when cutting the outfield.  The most common pattern is a chequerboard of stripes in the direction of play, crossed with stripes at right angles (90°) to the direction of play.  The width of the stripes is usually defined by two or three pitch widths on the square so that striping of the square can be lined up with the striping of the outfield.

You can use long string lines initially in the direction of play to set even stripe widths across the ground, cut these in and then to use the same stripe width at right angles to play.  Commonly these are two pitches (2 x 3.05 m = 6.10 m) wide. This creates a chessboard pattern of dark and light shades similar to Gingham cloth.

It is initially time consuming, but once the stripes are cut in, string lines are not required as long as the operator is skilled in driving in straight lines and aligning the edge of the cutting reel or rotary blades (and the mower rollers) to the edge of the bay as they cut.

The outfield can then be cut in alternating perpendicular cuts through the week.

It can take two or three cuts in a particular direction to get a good, bold stripe.

Striping is not necessary for play – it is only about visual presentation.  Outfields can be cut in a round pattern and are most commonly cut in a spiral pattern around the square (this is the quickest approach because stripe-edges do not have to be aligned.

Whichever approach you use, cutting the square in different directions helps to reduce nap of the grass leaf which can cause the ball to deviate across the outfield.

Benefits

• Regular cutting of the grass to the correct height helps ball roll and improves the performance of an outfield.
• Mowing frequently at the correct cutting height reduces the stress on the grass plant, avoids unsightly clumps of clippings that affect play and presentation and reduces that accumulation.
• Clean cutting of the grass plant results in a heathier sward – always set up your mower correctly.
• Improves presentation, which is the first thing players and officials see.
• Regular mowing helps to control some weeds which do not tolerate frequent close mowing

Practical tips

• Always perform pre-start checks on the mower, familiarise yourself with the user’s manual, follow all safety information and safe working practices.
• Check the cut on the mower before use and if necessary, adjust. A badly set mower will damage the grass plant, increase disease risk, increase the plant’s requirement for water and fertiliser, potentially damage the mower, or create excessive wear on parts.
• Make sure that all the cutting units are at the same height of cut.  If one unit is lower or higher than the others, you will see this as a narrow stripe and this will look unsightly and affect play.
• Reverse the direction of cut regularly to avoid creating too much of a nap.
• Clean the mower immediately after use.
• Lubricate and maintain the mower regularly to maintain optimum performance.
• As long as you are cutting frequently, you do not need to collect clippings.  Not collecting clippings increases work rates and reduces fertiliser demand.