The importance of ripping and scarifying the subsoil surface cannot be over emphasised
• The control and diversion of surplus drainage water from the immediate pitch surround is a matter often neglected. High ground above a pitch must shed water run-off on to pitches and the construction of cut- off drains, often as a late effort to save the situation, seldom save the situation in the long-term. Swales or diverting mounds and associated deep pipe drains prevent any surface water run-off or underground water from reaching the pitch. This measure alone can account for a good many of the problems faced on wet pitches.
• The location of a
permeable seam of gravel or depth of chalk can serve as a valuable means for water removal. The presence of a high water table is not usual on sports pitches but this has to be confirmed.
Sub-soil
A proper examination of the profile for the depth of a full two metres - or more where significant cut to fill procedures must be followed in construction - can reveal valuable information regarding the drainage in the lower layers.
• The application of gypsum and incorporation into the clay subgrade can considerably improve the drainage. In fact, the subsoil determines the drainage potential of the pitch and once the topsoil is in place its condition below the topsoil cannot be modified.
• The importance of properly ripping and scarifying the subsoil surface cannot be over emphasised.
• The preparation of the subsoil must be confined to dry weather conditions. Handling of any soil in wet conditions is damaging but preparation of a wet sub-base causes detrimental conditions that cannot be overcome.
Grading
The planning of the gradients can be a difficult task - especially on relatively level ground. With the inherent clay soils, wet winters with low evaporation rates, the surface condition easily becomes saturated.
• With topsoil in a saturated state and free water on or near the surface there is potential for water run-off provided there is sufficient gradient. From the playing perspective it is now well
established that the cross-fall can be as much as 2.5% while the gradient in the direction of play can be as much as 1.25%. Even without these gradients a diagonal fall of 1.45% should be relatively easy to obtain and this minimum grade is essential if surface water run-off is to be possible.
• Associated with the gradient is the evenness of the grade. Depressions in a pitch with good gradients soon concentrate surface water bringing waterlogged conditions. The final grading of the pitch is probably the most important requirement in the completion of a football pitch. Today with laser equipment even grades can be easily attained and the requirement of no variation greater than 25mm from the proposed grade and no greater than 15mm over a 3m straight edge anywhere on the pitch is not an unreasonable specification requirement.
Maintenance
The maintenance of a sports pitch for football must be aimed at sustaining a good dense grass cover over a period when there is not active growth. Naturally this
means that a systematic programme during the growing period is vital in achieving this condition.
• Basic nutrient formulations and follow up nitrogen treatments are relatively inexpensive and yet can become vital in securing a good ryegrass cover in preparation for the winter season.
• Mowing should be frequent enough to maintain a density in the grass cover. The interval should not be a fixed period but rather in accordance with the vigour in growth.
• Though not common on football pitches the control of thatch is essential. Being able to hold much water, thatch can initiate water- logged conditions.
• Decompacting by vertidraining or vibrating tines (such as the 'eartdhquake') is essential with continual play and the increasing compaction that takes place in the top 150mm of the topsoil. There are also the cultural treatments of harrowing, rolling and divoting.
• Weed control is often neglected. Weeds encroach
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