Cholla buds are the unopened flower buds of the cholla cactus (Cylindropuntia species), harvested in spring before they bloom, then de-spined and dried into a small, chewy, greenish-brown Southwestern vegetable. A traditional food of the Tohono O'odham and other Sonoran Desert peoples — who call them ciolim — the reconstituted buds have a tangy, artichoke-and-asparagus flavour and are prized as one of the most calcium-rich foods of the desert.