Sandy Loam Soil Class

This soil generally has more than half the particles being sand, so can be well drained yet also has a good quantity of silt and clay particles for nutrient and moisture retention. An example of a sandy loam soil is one that contains the following: 60% sand, 25% silt, 15% clay. This type of soil is well suited for general sports grounds and playing fields.

  Sandy Silt Loam Soil Class

A soil with a high percentage of sand and silt compared with clay and can be suitable for general lawns or landscape areas, although not for sports turf situations as smearing of the surface layer and within the profile can be a particular problem. An example of a sand silt loam soil is one that contains the following: 30% sand, 55% silt, 15% clay.

  Saturated Water Content

All, or almost all, pore spaces are filled with water. A saturated soil will produce surface puddles when further water is added, this is called ‘ponding'. The term is also referred to as Saturation, Saturated Soil, or Saturation Point.

  Seed Bed

A prepared area of soil which is even and has a fine tilth, free of stones and debris, and which is ready for grass seed to be sown.

  Shallow Soil

A relatively thin topsoil overlying a subsoil. This can be typical of natural soils in chalk areas or what many builders will leave following new housing builds.

  Silica

A common mineral component of many sands. Its chemical composition is silicon dioxide (SiO2) and this is usually represented as quartz. It is chemically inert, hard and relatively resistant to weathering.

  Silt

A fine granular, silky to feel when moist, mineral with particles between sand and clay, with size ranges varying according to the scale used: The International Scale, or the US (known as Udden¯Wentworth) scale.

  Silt Loam Soil Class

A soil with a high percentage of silt, along with high quantities of sand and medium quantities of clay. An example of a silt loam soil is one that contains the following: 5% sand, 82% silt, 13% clay. It can compact very easily, yet does retain nutrients and water well, so for general landscape areas this might be suitable, although usage on slopes may be inadvisable due to potential stability issues with high silt soils.

  Silt Soil Class

This soil contains a very high amount of fine silt particles, being smooth and silky to touch and is especially powdery when dry as the particles do not hold together well like a clay soil does. An example of a silt soil is one that contains the following: 10% sand, 85% silt, 5% clay. A silt soil can retain nutrients and water and is often present in river valleys, being more noticeable on flood plains and areas that are temporarily flooded from overflowing rivers. There is not a stand-alone silt textural class in the UK Soil Textural Triangle as this is all enclosed within the silt loam class.

  Silt Trap

An inspection chamber within a drainage system. The chamber allows soil sediment, that is suspended or contained within drainage water for a period of time, to settle in the base of the chamber. Less contaminated water will eventually be discharged in the outflow pipes once the height of those pipes has been reached. It is important to periodically inspect and clean out silt traps, otherwise sediment will build-up and clog up the drainage system, making it ineffective. It is also called an inspection chamber.