What Lives in Soil?

Here are a few of the living organisms that live in soil:

The Night Crawler
Lumbricus terrestris

Length: 9-30 cm
Life span: 3-6 years
Population: several in each shovel of soil.
-Night crawlers eat any dead organic matter they come across. They don't have any teeth and eat the soil as they move along. Any microscopic animal in the soil becomes worm food. The bacteria in their stomach grow and increase in number making the soil healthier.

Beetle Mite
Oppia sp.

Length: 0.2 - 0.3 mm

Life span: 6-12 months

Population: 600,000 per square meter
-Beetle mites have no eyes. They break down organic matter into humus and only eat fungus. Likewise, when they die their bodies join the chain of minerals that they carry themselves when they were alive.

Bacteria

Length: 0.001 - 0.005 mm
Life span: divides into two new bacteria
every 20 minutes.
Population: about 1,000 trillion per square meter. "over 1,000 could fit across the head of a pin."
-There are thousands of species of bacteria. The oldest living things, these single celled bacteria are decomposers. These organisms are an important part of the life in the soil. "They recycle the energy stored in dead organic matter back into plant food'

Nematode (Round worm)
Acrobeles ciliatus

Length: 0.3- 1.5 mm

Life span: unknown

Population: 30 million per square meter. "5,000 in one teaspoon of soil"
- The nematodes move through the thin film of water between the soil particles. The only members of their group, these multi-cellular animals live all around the world. They eat bacteria's by digesting them in their stomachs while other roundworms eat dead organic matter. However, the roundworms that eat and live in plant roots can damage those plants.

Eastern mole
Scalopus aquaticus

Length: 13-20 cm long
Life span: 3 years
Weight: 54-99 grams
Population: many in an acre
- Eastern moles dig through the soil, making it looser and more healthier. They eat earthworms and insect larvae. Digging all the time they get tired so they need food half of their body weight everyday. They dig burrows under moist, sandy soil where they raise their young, use for sleeping and use it as a home.

All images used with permission from: Saskatchewan Interactive