B. Collembola - springtails lacking metamorphosis primitively wingless. Common in grassy or wooded habitats worldwide. Economic Importance break down and recycle organic wastes. A few species feed on living plants and are occasionally regarded as pests: damage seedlings in early spring, pest of alfalfa in Australia, frequent pest of commercial mushrooms.
In winter, snow fleas emerge on sunny days and gather in large numbers around bases of trees where snow has melted. Because of their small size, they look like flecks of pepper or ashes on the surface of the snow. Snow fleas feed on decaying plant matter.