Tiny creatures improve soil for crops

Agriculture

Notes to broadcasters

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Content: The soil is full of living creatures that make food for crops and improve the soil.

Notes

In this item. we mention that one of the benefits of organic matter is that it supports the life of microbes living in the soil. Adding organic matter soil also improves the soil’s water holding ability and structure. Other DCFRN scripts which refer to the benefits of adding organic matter are:

Fertilizer from paddy straw – Package 6, Item 5

Improving manure – Package 8, Item 3

Trench-bed gardening for drylands – Package 9, Item 1

Making your own compost – Package 15, Item 9

Manure, a good source of plant food = Package 18, Item 2

Script

HOST:
The soil beneath your feet is the home of millions of living creatures. In fact, scientists say that there are more living beings under the ground than above it. These include small animals, insects, earthworms, and termites. There are also soil microbes* so small we can’t see them. Although often forgotten, they are very important for agriculture.

These soil creatures are working all the time, improving the condition of the soil and making food for plants. Today, let’s think about some of these creatures that are so important to soil, plants, and agriculture in general.

Earthworms, insects, spiders

Earthworms, insects, and spiders, are just some examples of the little soil creatures that you can see. Most of these make holes or burrows as they move through the soil. These holes provide space in the soil where plant roots can grow, and water can move more easily. Earthworms eat small particles of soil and bits of dead plants and animals, mix them together inside their bodies, and then leave behind waste that is full of nutrients. In this way, they help to cultivate the soil. Many types of spiders also live in the soil. Spiders are good because they kill many crop pests.

* Soil microbes are organisms living in the soil that are so small they can only be seen with a microscope. These include microflora such as fungi, bacteria, and actinomycetes, and microfauna such as nematodes and protozoa.

Soil microbes

Soil microbes are very tiny living creatures that you can only see through a microscope. It is hard to believe how many of these microbes exist and that they have so many shapes, sizes, and colours.

Imagine that the soil is the “workshop” of these soil microbes. Each microbe has a special job in the workshop, and all are necessary for a healthy soil and healthy plants.

For example, some soil microbes feed on dead plants and animals and change them into food that your crops can use to grow. Other helpful soil microbes take nitrogen from the tiny air spaces between soil particles and change it into food for plants. There are even microbes (fungi) which attack and eat nematodes. You may know that nematodes are tiny worms, and some of them are bad for crops because they eat plant roots. Perhaps the most important thing to remember is that, although soil microbes work in many different ways, nearly all of them help to make food for crops.

In a sense, these tiny creatures are working for you since crops grow better because of their activity. Like all living things, however, they need food, water, and air so you have to feed them. You have to give them the right food. They eat organic matter. By adding organic matter to the soil, you provide food for microbes, which in turn make food for crops.

How can you add organic matter to the soil? These are some of the things you can do to add organic matter to soil: mix compost with your soil regularly, put mulch on the soil, return crop residues to the soil, add animal manure, rotate crops, and use cover crops and green manure. All these practices add organic matter to the soil.

It is important to remember that a large part of the soil is made up of these tiny, living, helpful creatures. So, think carefully about how different things you add to the soil might affect them. It is too bad that many of these helpful creatures are killed when too many chemical fertilizers and pesticides are used.

Remember, if you want all those soil creatures working for you, be sure that there is lots of organic matter in the soil. More organic matter means more creatures in the soil which will, in turn, make more food for your crops. A farmer who adds lots of organic matter to the soil, such as crop residues, compost, and manure, will find that the soil is easier to cultivate, the soil is more fertile, and the crops better and more plentiful.

 

Information sources

1. Soil management and improvement, pages 27-46 of Intensive vegetable gardening for profit and self-sufficiency, Peace Corps, Washington, D.C., U.S.A. https://pclive.peacecorps.gov/pclive/index.php/pclive-resources/resource-library/1279-r0025-intensive-vegetable-gardening/file