Prunus padus, known as bird cherry or hackberry, is a species of cherry, native to northern Europe and northern Asia. It is a deciduous small tree or large shrub, 8-16 m tall, which grows south of the Arctic Circle in northern Britain and Ireland, Norway, Sweden, Finland, Russia and Ukraine. There are also some trees in France, Spain, Portugal and in the Balkans. It is the type species of the subgenus Padus, which have flowers in racemes.
The English name "hackberry" refers to the fruit, which is astringent due to their tannin content.
There are two varieties:
The flowers are hermaphroditic and pollinated by bees and flies. The fruit is readily eaten by birds, which do not taste astringency as unpleasant.
Bird-cherry ermine moth (Yponomeuta evonymella) uses bird-cherry as its host plant, and the larvae can eat single trees leafless.
The glycosides prulaurasin and amygdalin, which can be poisonous to some mammals, are present in some parts of P. padus, including the leaves, stems and fruits.
The fruit of this tree is seldom used in western Europe, but is commonly eaten farther east.
The blacks fruits of the tree can be ground down to make flour for culinary purposes.
It was used medicinally during the Middle Ages.[clarification needed]
The bark of the tree, placed at the door, was supposed to ward off plague.[clarification needed]
It is also sold as an ornamental in North America as a May Day tree.[clarification needed]
A taboo on the use of the wood was reported by natives of Advie, in northeast Scotland, being regarded as a "witches tree".