Soils and drainage

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An open channel or ditch which allows water, especially excess water, to flow from a field or drainage system.

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A Calcium Sulphate mineral which has been used as a fertiliser on sodic soils. It is also sometimes called Sulphur of Lime.

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The Humic or Humus horizon within a soil profile. Where present, it forms part of the O Horizon.

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The rubbing of slightly moist soil between fingers and thumbs to estimate the general soil type: especially if it is sandy (having a gritty feel); if it is silty (having a silky and smooth feel); or clayey (having a sticky feel to it). See also Soil Texture.

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A concrete, brick, or similar, wall which is built around a major drainage outfall pipe. The main aim of a headwall is to provide stability to outfall situations.

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A drainage system where the lateral drainage trenches and pipes are installed in a fishbone type pattern. A central main drain is connected to by the lateral drains which are staggered and alternate along the length of the main drain. The lateral trenches will typically join a central drain at an angle of about 60 degrees.

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A scientific method for determining the spacing requirements of pipe drainage or sand-gravel slit drainage in a sports field situation.

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Part of the Organic Horizon which consists of well decomposed plant material. A Humic/Humus layer would sit below a Fermentation layer, and above an A Horizon. t is also called the H Horizon/Layer/Zone.

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Reinforced rootzone with inclusions added to aid pitch stability.

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A measure of the rate of water flow, typically saturated water flow, through the soil. In very general terms this might be thought of as indicative of a soils potential drainage rate. Hydraulic conductivity (HC) is influenced by a number of different factors, including: • The water content of the soil. A drier soil will have a lower HC, with the soil typically needing to reach field capacity before any significant outflow of water is achieved. HC is at its maximum when a soil is saturated. • Water and soil temperature affect the rate of flow. A warmer water is more fluid (i.e. having a

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