First, because of the heavy yin, and second, because most of the people who planted willow trees in front of the grave are the graves of ordinary people, there won't be any valuable funerary objects.
there is a folk saying that it is a bad style, that is, willow trees are full of yin. Grave robbers have a high respect for ghosts and gods, although they do the wicked thing of smashing people's ancestral graves. Grave robbers also have their own views on the five elements of Feng Shui, and they also know that they can't go to places where Yin Qi is too heavy, but this statement has no historical basis. However, there is also a saying that ancient people did not build tombs at will. In addition to the limitation of building scale, even the trees planted next to the tomb are also very particular. The trees planted next to the tomb are selected according to the identity of the tomb owner.
In ancient times, only people who were really poor enough to eat would rob tombs because they were very reluctant to do so. Ancient people's thoughts were originally feudal and superstitious. However, there is a kind of tomb that they will not go to no matter how difficult it is, and that is the tomb with willows in front of the door. Mainly because there is an unwritten rule in the grave robbery industry. If you steal this tomb, it will be looked down upon by people in the industry. When the ancients died, they had a habit of planting a tree in front of the tomb, and the tree was not planted casually, but according to its identity. When members of the royal family plant pine trees, princes and nobles generally plant cypress trees, while willow trees are only planted by the poor.
These grave robbers entered the tomb mainly for money, not for destruction. Therefore, when a grave robber sees a willow tree, he knows that the owner of the tomb is a civilian, and there won't be anything of value in it, so he won't rob the tomb. The ancients thought that willow was a tree of five ghosts, which gathered a lot of shade, so there might be ghosts in Liu Xia. So the grave robbers looked at the willow tree in front of the tomb and thought that if they stole the tomb, they might encounter ghosts. The above two points are the reasons why grave robbers dare not steal willow graves. On the one hand, it is unprofitable, on the other hand, it is also influenced by feudal superstition. To some extent, the willow trees in front of the tomb are also guarding the tomb.
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