Pyracantha ('from Greek pyr fire and akanthos a thorn' hence firethorn) is a genus of large, thorny evergreen shrubs in the family Rosaceae, with common names firethorn or pyracantha. They are native to an area extending from Southwest Europe east to Southeast Asia. They resemble and are related to Cotoneaster, but have serrated leaf margins and numerous thorns (Cotoneaster is thornless). The plants reach up to 6 m (20 ft) tall. The seven species have white flowers and either red, orange, or yellow berries (technically pomes). The flowers are produced during late spring and early summer; the berries develop from late summer, and mature in late autumn. A large number of fossil fruits of †Pyracantha acuticarpa have been described from middle Miocene strata of the Fasterholt area near Silkeborg in Central Jutland, Denmark. Selected cultivars (those marked .mw-parser-output .smallcaps{font-variant:small-caps}agm have gained the Royal Horticultural Society's Award of Garden Merit): Pyracanthas are valuable ornamental plants, grown in gardens for their decorative flowers and fruit, often very densely borne. Keep in mind the extremely difficult and painful process to prune and maintain the shrubs. The thorns are easily able to puncture human skin, and when successful, the piercing causes a slight inflammation and severe pain. Their dense thorny structure makes them particularly valued in situations where an impenetrable barrier is required. The aesthetic characteristics of pyracanthas, in conjunction with their home security qualities, make them an alternative to artificial fences and walls. They are also good shrubs for a wildlife garden, providing dense cover for roosting and nesting birds, summer flowers for bees and an abundance of berries as a food source. Pyracantha berries can be dispersed into natural areas, allowing plants to invade natural communities. Species of Pyracantha are considered to be invasive in portions of the United States, including the states of California and Georgia. Orange firethorn (Pyracantha angustifolia) is considered to be a weed or potential ('sleeper') weed in several states or territories of Australia, including Victoria, the ACT and New South Wales. As a consequence, importation and propagation are prohibited in some parts of Australia. The fruit of Pyracantha are classified as pomes. The pulp is safe for human consumption, but it is insipid, and the seeds are mildly poisonous as they contain cyanogenic glycosides (as do apples, plums, cherries, and almonds). Seeds that are chewed and crushed while raw will release cyanogenic glycosides, and can cause mild gastro-intestinal problems when eaten in large enough quantities. The fruit can be made into jelly. In the UK and Ireland Pyracantha and the related genus Cotoneaster are valuable sources of nectar when often the bees have little other forage during the June Gap.