Sacred groves are under-researched in Muslim countries so that their overall contribution to biodiversity conservation remains unknown. We studied 22 sacred groves and 45 surrounding woodlands in Northern Zagros, Iran, to compare taxonomic diversity, vegetation composition, and the conservation status of plant species. Sacred groves had higher taxonomic diversity and a more valuable species pool by sheltering numerous endangered plant species. Multivariate analysis indicated a substantial difference in the vegetation composition of sacred groves and surrounding woodlands. Traditional deliberate protection (because of religious values) plus some environmental variables were the main drivers of the distinct vegetation composition of sacred groves. Sacred groves are the only remains of old-growth forests in the border regions of Iran and Iraq and they are important refuges of biocultural diversity. To better link the conservation of nature and culture, we recommend encouraging local people to preserve spiritual values, myths, and taboos around sacred groves.
