Look closerInsects
Snow fleas: the hopping specks on melting snow are springtails
When: January to March
On a thawing late-winter day the snow around tree trunks can look dusted with pepper, and the pepper hops. They are springtails, a tenth of an inch long, and they have been under the leaf litter all winter with antifreeze in them.
Why this time of year
They live in soil and leaf litter year round and come up through cracks in the snow in late winter as it starts to melt, which is the only time of year most people ever notice them. Sometimes in numbers that turn a patch of snow black.
How to notice it
- Pick a thawing day and look at the snow right against the base of a tree. That is where they gather.
- Get down close. At a tenth of an inch they read as specks of dirt until one moves.
- Watch for the jump. They do not have legs for it: a forked appendage is held under tension against the body and released like a catch, which flicks them several inches.
- Wave a hand over them and watch the patch scatter, then reassemble.
Try this with kids: Look at the dark specks on the snow for ten seconds without blinking. Do any of them move?
a springtail is a tiny soil animal that jumps with a spring-loaded fork tucked under its body
Safety
- Harmless. They do not bite, they are not fleas, and they are good news for the soil they came out of.
Sources
- entomology.umn.eduUniversity of Minnesota entomology: snow fleas are springtails, about 1/10 inch long and dark blue-grey, wingless, with a forked appendage called a furcula held by a clasplike retinaculum which when released propels them up and forward several inches; they live in soil and leaf litter and come to the snow surface in late winter as the snow starts to melt, moving through cracks in the snow, sometimes in numbers that literally turn snow black, especially near tree bases; they eat microscopic fungi, algae and decaying organic matter; they are harmless and beneficial; they possess an antifreeze protein; they are occasionally attracted to maple syrup during sap harvesting
In the guide for January, February, March