Soil Classification

Sandy soil              Building sand

                                Particles  > 0.2mm in diameter.

                                Texture is coarse and gritty when rubbed between two fingers.

                                Particles are loosely arranged.

                                Soil is well aerated.

 

Loam soil               Garden soil

                                Particles of different sizes, usually between 0,02mm - 0.2mm.

                                Contains humus and dead organic matter.

                                Texture varies from fine clay to coarse sandy particles.

                                Sandy loam for example can be well aerated.

                                May contain variety of soil organisms, worms, fungi and bacteria.

                                Loam with a lot of silt can have a soapy feel.

 

Clay soil                 Bishops Pre-prep.

                                Particles are very fine, < 0.02mm.

                                Dense heavy soil.

                                When moist can be rolled into a sausage

 

Experienced soil scientists can classify soil just by rubbing it between their fingers!

Instructions:

• In this practical you are going to learn how to classify soil samples from three different sites, according to size and learn to feel different soil textures.
• Write down all observations you make in the space provided below.

Method: 

1. View your soil samples using a hand lens.
2. Observe the particle sizes according to the information on page 7 and 9 of the notes.
3. Observe any other characteristics regarding the soil type (organic matter content, aeration of soil).
4. Damp the soil with a few drops of water and feel the soil samples between your fingers.

Note down your observations on soil texture of the soil samples.

RESULTS:

 

1. Write down your observations on the soil texture of the 3 types of soil.

 

1. Soil sample 1

Loam soil – It has fairly large particles and a dark colour. It feel really rough and you can feel the different sized particles

 

2. Soil sample 2

The soil has little air cavities and the particles are packed closely together. It has a smooth texture when felt.

 

3. Soil sample 3

The soil has mainly one size particles and has no water retention capacity with air pockets. It is a ‘sandpaper’ type of texture and feel.

 

2. How would you classify (sandy, loamy or clay) Soil sample 1-3?

 

Soil sample 1 is Loamy

 

Soil sample 2 is Clay

 

Soil sample 3 is Sandy