What is mud?

Mud forms when soil is mixed with water. Soil is ) made up of grains of sand and dust that have
been worn away from rocks. Soil also contains many little bits of dead plants and animals. This organic material in soil—called humus—is what makes it rich in food for plants and animals.
Soil can become mud when large animals
trample in a rain pool. Sand grains, dust and
humus from the soil become stirred into the water together. When the animals go away and
the pool becomes still, the heavier sand grains sink to the bottom quickly But the fme grains and
humus may take several days to settle and form a
layer of mud on top of the sand. The mud contains most of the humus that was in the soil and so it is rich in plant food, but the constant trampling stops ajiy plants from growing around the pool.