Prunus apricots, of cherries, and of plums, all of which have cultivars developed for commercial fruit and nut production. The almond is not a true nut, the edible part is the seed. Other species are occasionally cultivated or used for their seed and fruit. A number of species, hybrids, and cultivars are grown as ornamental plants, usually for their profusion of flowers, sometimes for ornamental foliage and shape, and occasionally for their bark. The Tree of 40 Fruit has forty varieties grafted on to one rootstock. Species such as blackthorn ("Prunus spinosa"), are grown for hedging, game cover, and other utilitarian
Prunus argentea lengthens to 2 to 7mm when the fruit is fully developed. It is found growing in a variety of habitats; open oak woodlands, rocky slopes, dry silted areas, and steep banks of streams, at 500 to 2000m above sea level. A genetic study showed that its closest relative is probably "Prunus haussknechtii". In warmer areas of Europe it is occasionally cultivated as an ornamental garden plant for its fragrant rose-pink flowers and attractive foliage, but it must be planted in a protected spot for best results. Prunus argentea Prunus argentea, sometimes called the silver almond, is a species of wild