What do you mean by ancient piles?

Ancient piles can be used to make large pile landscapes, which is a good product for bonsai lovers and landscaping. The ancient piles are smooth, with many nodules and cavities, and the appearance is simple and vigorous. There are fresh green leaves and flowers on the dead wood, which are of high ornamental value. However, most of Wei Zi's ancient piles are ancient trees that have grown for hundreds of years, and they are natural heritages that cannot be copied artificially.