Can dead wood germinate? Why can it sprout? Principle?

Some "dead wood" can germinate. Because there are buds on the bark, under suitable temperature and humidity conditions,

At that time, the buds on the bark may be elongated, and the nutrients in the cortex can be used to grow for a period of time, but not for a long time.

For a long time, because the dead wood is rotten, it is dead and rotten after all.