I dreamed that the tree was knocked down by lightning.

According to the Duke of Zhou, dreaming of thunder means that something unlucky is going to happen. Trees represent their own bodies, and trunks are trunks.

So this dream of yours may indicate that there is something wrong with your body and you need to go to a regular hospital for a general examination.

Of course, I'm not spreading superstition, but physical examination is always good for me. Don't worry, go and have a look.