What are the signs of nature in spring?

I'm from the northeast. When I was young, I heard my elders say that people can't walk on the ice after spring begins. Later, I understood: beginning of spring is the solar term of the Spring Festival. When the ice freezes, it freezes layer by layer, but when it melts, it melts into vertical strips because of the upward geothermal airflow. So that people can easily get stuck when they go up. So there is the saying that "the ice turns to stubble".

I heard from my grandmother that I didn't do any experiments with the landlord. Grandma said she played this game when she was a child. She put a thin bamboo tube into the soil and then threw a handful of dried chicken feathers. If before beginning of spring, chicken feathers fell on the soil of bamboo tubes and froze; After beginning of spring, he couldn't throw it in, as if someone was blowing at the other end.