Ways to tell the direction in rainy days:
1. Independent trees usually have lush branches and smooth bark in the south and sparse branches and rough bark in the north. In the south, the grass is usually dense, and in the north, it is humid and covered with moss.
2. In China, if there is snow in the valley, the first side of the mountain to melt snow is the sunny slope (the slope facing south), and the other side is the opposite.
3. The doors and windows of large temples in northern China, pagodas in plain areas and independent houses in rural areas are mostly open to the south.
4. The big rivers in China generally flow from west to east, and the direction can generally be determined.
5. The grass is dense on the northern edge of the open space in the forest. Tree rings on the cross section of stumps are generally spaced apart in the south and small in the north.