As described in historical dictionaries

Patronymica Britannica (1860)

PLANCHE. Probably of Norman origin. There are three places in the province, called Planches-sur Iton, Planches-sur-Rile, aud Planchez-Mellerai, situated respectively in the arroudissements of Louviers, Argentan, and Avranches.

Lower, Mark A (1860) Patronymica Britannica: a dictionary of the family names of the United Kingdom. London: J.R. Smith. Public Domain.


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