What is the difference between loamy sand and sandy loam

Now let it stand undisturbed for some time. The rotting dead matter in the soil is called humus. You probably know that the soil is formed by the breaking down of rocks by the action of wind, water and climate.

This process is called weathering. The nature of any soil depends upon the rocks from which it has been formed and the type of vegetation that grows in it.

A vertical section through different layers of the soil is called the soil profile. Each layer differs in feel texture , colour, depth and chemical composition. These layers are referred to as horizons. We usually see the top surface of the soil, not the layers below it. If we look at the sides of a recently dug ditch, we can see the inner layers of the soil, too. Such a view enables us to observe the soil profile at that place. Soil profile can also be seen while digging a well or laying the foundation of a building.

It can also be seen at the sides of a road on a hill or at a steep river bank. The uppermost horizon is generally dark in colour as it is rich in humus and minerals. The humus makes the soil fertile and provides nutrients to growing plants.

This layer is generally soft, porous and can retain more water. It is called the topsoil or the A-horizon. This provides shelter for many living organisms such as worms, rodents, moles and beetles. The roots of small plants are embedded entirely in the topsoil. The next layer has a lesser amount of humus but more of minerals. This layer is generally harder and more compact and is called the B-horizon or the middle layer. The third layer is the C-horizon , which is made up of small lumps of rocks with cracks and crevices.

Below this layer is the bedrock , which is hard and difficult to dig with a spade. As you know, weathering of rocks produces small particles of various materials. These include sand and clay. The relative amount of sand and clay depends upon the rock from which the particles were formed, that is the parent rock. The mixture of rock particle sand humus is called the soil. Living organisms, such as bacteria, plant root sand earthworm are also important parts of any soil.

The soil is classified on the basis of the proportion of particles of various sizes. If soil contains greater proportion of big particles it is called sandy soil. If the proportion of fine particles is relatively higher, then it is called clayey soil. If the amount of large and fine particles is about the same, then the soil is called loamy. Thus, the soil can be classified as sandy, clayey and loamy.

The sizes of the particles in a soil have a very important influence on its properties. Sand particles are quite large. They cannot fit closely together, so there are large spaces between them. These spaces are filled with air. We say that the sand is well aerated.

Water can drain quickly through the spaces between the sand particles. So, sandy soils tend to be light, well aerated and rather dry. Clay particles, being much smaller, pack tightly together, leaving little space for air. Unlike sandy soil, water can be held in the tiny gaps between the particles of clay.

So clay soils have little air. But they are heavy as they hold more water than the sandy soils. The best topsoil for growing plants is loam. Loamy soil is a mixture of sand, clay and another type of soil particle known as silt.

Silt occurs as a deposit in river beds. The size of the silt particles is between those of sand and clay. The loamy soil also has humus in it. It has the right water holding capacity for the growth of plants. Collect samples of clayey, loamy and sandy soils. Take a fistful of soil from one of the samples. Remove any pebbles, rocks or grass blades from it. Now add water drop by drop and knead the soil. Add just enough water so that a ball can be made from it, but at the same time it should not be sticky.

Try to make a ball from this soil. On a flat surface, roll this ball into a cylinder. Try to make a ring from this cylinder. Repeat this activity with other samples also. You have listed some uses of soil.

Let us perform some activities to find the characteristics of the soil. Boojho and Paheli marked two different squares of 50 cm - 50 cm each, one on the floor of their house and the other on the kutcha unpaved road. They filled two bottles of the same size with water. They emptied the water from the bottles, one each, at the same time in the two squares.

They observed that the water on the floor flowed down and was not absorbed. On the kutcha road, on the other hand, the water was absorbed. For this activity divide yourself into three teams. Name the teams A, B and C. You will be finding out how fast the water passes down the soil. You will need a hollow cylinder or a pipe. Ensure that each team uses pipes of the same diameter. Some suggestions for obtaining such a pipe are given below.

At the place where you collect the soil, place the pipe about 2 cm deep in the ground. Pour mL water in the pipe slowly. For measuring mL water you can use any empty mL bottle. Note the time when you start pouring water. When all the water has percolated leaving the pipe empty, note the time again. Be careful not to let the water spill over or run down on the outside of the pipe while pouring. Calculate the rate of percolation by using the following formula:.

For example, suppose that for a certain sample, it took 20 minutes for mL to percolate. Calculate the rate of percolation in your soil sample. Compare your findings with others and arrange the soil samples in the increasing order of the rate of percolation.

Have you ever passed through a farmland during a hot summer day? Perhaps you noticed that the air above the land is shimmering. Why is it so? Try out this activity and find the answer.

Take a boiling tube. Put two spoons full of a soil sample in it. Heat it on a flame and observe it. You can determine whether your yard has this kind of soil using a simple test. Sandy loam soils are broken down into four categories, including coarse sandy loam, fine sandy loam, sandy loam and very fine sandy loam.

The size of the sand particles is measured in millimeters and their concentration in the soil is used to determine which category a soil falls under. Sandy loam soils are made of approximately 60 percent sand, 10 percent clay and 30 percent silt particles.

Sandy loam soils have visible particles of sand mixed into the soil. When sandy loams soils are compressed, they hold their shape but break apart easily. Sandy loam soils have a high concentration of sand that gives them a gritty feel.

In gardens and lawns, sandy loam soils are capable of quickly draining excess water but can not hold significant amounts of water or nutrients for your plants.

Plants grown in this type of soil will require more frequent irrigation and fertilization than soils with a higher concentration of clay and sediment. Sandy loam soils are often deficient in specific micronutrients and may require additional fertilization to support healthy plant growth.

You can quickly identify sandy loam soil based on its physical characteristics. Pick up a handful of dry soil and slowly dribble water onto it.