Brassica napus subsp. rapifera. Rutabagas, long used as a forage crop for sheep and cattle in France, usually appear in the supermarkets around October. Like Jerusalem artichokes (topinambours) many elderly French people associate them with the hard times of the Second World War and never want to see them again. But they are making a comeback.
The French have a lot of other names for them: navet fourrager, navet, chou-navet, chou de Siam or chou suédois.
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