Ferocactus glaucescens

Ferocactus glaucescens is a solitary or branching cactus with spherical or cylindrical blue-green frosted shoots, growing up to 45 cm (18 in) in height and 60 cm (24 in) in diameter. The shoots have slightly depressed apices and 12 to 17 sharp-edged, non-tuberculated ribs with elongated areoles that are often connected. Its yellow spines, which are difficult to distinguish between central and peripheral, can reach up to 3.5 cm (1.4 in) in length, with one central spine and 6 to 7 radial spines.

The bell-shaped, yellow flowers of Ferocactus glaucescens are up to 4.5 cm (1.8 in) long and 2.5 to 3.5 cm (0.98 to 1.38 in) in diameter. Its spherical, whitish or yellowish, red-tinged fruits are fleshy, reaching lengths of up to 2.5 cm (0.98 in) and covered in yellowish, ciliated scales.^[2][3]

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  Adult Plant
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  Flowers
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  Flower and buds

This species is native to the limestone hills and dry forest of Hidalgo, Guanajuato, Querétaro, and San Luis Potosí states of Mexico at elevations of 550 to 2300 meters.^[4]

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  Plant growing between limestone south of Caricillo towards Xichu, Guanajuato
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  Plant growing in habitat south of Caricillo towards Xichu, Guanajuato
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  Habitat in Gilo, Hidalgo

First described as Echinocactus glaucescens in 1828 by Augustin Pyramus de Candolle, the specific epithet "glaucescens" comes from the Latin words "glaucus" for 'blue-green' and "-escens" for 'becoming', referring to the color of the shoots.^[5] In 1922, Nathaniel Lord Britton and Joseph Nelson Rose reclassified it into the genus Ferocactus.