Have you ever noticed the different textures in
soils? Rub some soil between your finger and thumb to see. Try
this in different areas as a comparison.
Textures come mainly from the size and amount of mineral particles
present in the soil. For example, if you try picking up a handful
of a sandy soil, you will notice that it feels ‘gritty’.
This is because it is made up of large mineral particles. Compare
this to a handful of clay soil, which feels sticky to touch when
wet because it has finer particles which can hold more water. Silty
soils lie in composition between sandy and clayey ones and have
a smooth somewhat velvety feel to them.
Organic matter, also called humus, believed by many to be the
most important constituent of soils, is partially-decomposed organic
material, rich in nutrients, which is essential to the fertility
of soil (or how fruitful and productive it is). You can often tell
how much organic matter there is in soil by looking at how dark
it is – the darker the soil, the greater the concentration
of organic matter.
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