[livi]

Sorry. I donīt know the terms in English. There are many 'cultivated' forms of threes, that differ from the trees original shape of growing. Miniatures, hanging, different colors etc. I donīt know what species your tree is, but that shape of growing is not natural. Its a kind of genetic fluke, thats been cultivated to grow in that manner.

Many trees, typically fruit of all kinds, like apple trees, have a root and base stem from a tree with good, resilient characteristics. Now, from the base of the stem you literary cut and paste another subspecies onto the original so they grow together during infancy. The upper part, with all the branches and leaves, having special characteristics (for example hanging branches).

Sometimes the original stem part sprouts new shoots that will have the characteristics of the original tree (for example with branches growing upward).