A fruit tree is any fruit-producing tree, the structures of which form the mature egg of a flower, contain one or more seeds. However, since in order to know it, they have to relate in a large amount since all flowering plants produce fruit, the term used in horticulture designates trees that provide fruit as food for humans. This designation also includes trees that produce nutlets (walnuts), the so-called nuts. Although botanically incorrect, trees that produce fleshy coverings on certain seeds, called aril (false fruit), are also often considered fruit trees. The scientific discipline and cultivation of fruits is called pomology, and is primarily focused on cultivation techniques and physiological studies on fruit trees.