Bromus interruptus, commonly known as the interrupted brome, is a flowering plant in the grass family. It is endemic to southern and central England, which became extinct in the wild in 1972. After several decades in cultivation, the interrupted brome was re-introduced to Aston Rowant National Nature Reserve in 2004, marking the first known re-introduction of an extinct plant in Britain. The plant was a weed of waste places and arable agriculture, particularly of sainfoin (Onobrychis viciifolia) cultivation. It can be distinguished from all other Bromus species by its deeply split, or bifid, palea.

The plant appeared to spread rapidly after its discovery in 1849, which is normally indicative of introduced species. However, the species is thought to have arisen in the 19th century as a new species through a substantial and abrupt genetic change. It is thought to have gone into decline with the replacement of horses by motor vehicles from the late 19th century onwards, reducing the demand for sainfoin as fodder, and additionally by improved seed cleaning methods.

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