||This article needs to be wikified. (May 2016)|
Humus is dead plant and dead bug (insect) parts in the soil. When plants and insects die they are called raw "organic matter". When raw organic material is in the soil very, very small living things called bacteria and fungi can eat it. The bacteria and fungi eat the raw organic matter, but they do not eat all of it. They leave a very small part of the organic matter behind. The part they leave behind is called "humus". Humus is the part left when the bacteria and fungi are done eating. Humus is very good for plants because it is like a sponge. The humus takes in water and plant food (nutrients). The humus is mixed in the soil and is hard to see. If you could put a lot of it in your hand, it would look like a soft grey blob. Plants put roots in the humus to get food and water.