Crataegus monogyna, known as common hawthorn or single-seeded hawthorn, is a species of hawthorn native to Europe, northwest Africa and western Asia. Other common names include may, mayblossom, maythorn, quickthorn,whitethorn, motherdie, and haw. The Common Hawthorn is a shrub or small tree 5–14 m tall, with a dense crown. The bark is dull brown with vertical orange cracks. The younger stems bear sharp thorns, 1 to 1.5 cm long. The leaves are 2–4 cm long. The hermaphrodite flowers are produced in late spring, the haw is a small, oval dark red fruit about 1 cm long, berry-like.
Crataegus monogyna is one of the most common species used as the hawthorn of traditional herbalism, which is of considerable interest for treating cardiac insufficiency by evidence-based medicine. The plant parts used medicinally are usually sprigs with both leaves and flowers, or alternatively the fruit. It is a good source of antioxidant phytochemicals. The fruit of hawthorn, called haws, are edible raw but are commonly made into jellies, jams, and syrups, used to make wine, or to add flavour to brandy. Botanically they are pomes, but they look similar to berries. A haw is small and oblong, similar in size and shape to a small olive or grape, and red when ripe. Haws develop in groups of 2-3 along smaller branches. They are pulpy and delicate in taste. In this species (C. monogyna) they have only one seed. Petals are also edible, as are the leaves, which if picked in spring when still young are tender enough to be used in salads.