Which one is more resistant to decay, apricot, chestnut or pine?

Pine.

Pine wood is generally durable outdoors for three years. Pine wood is an oily wood that is generally not easy to rot.

The fatal injury of pine wood is the fear of insects. The most fearful thing is that in a dark and humid environment, white ants will appear immediately in hot and humid weather. These white ants basically last for two or three years. Completely rot a pine tree with a diameter of one meter.