As a Southern California resident, I am keenly aware of the long-standing droughts the region has had for the last several decades. I remember being in southern England during a drought emergency when it hadn't rained for three months. Here, I've seen it go ten years without more than a few inches per year, if that. Residents are volunteering to de-sod their yards, replacing the grass with its imitation counterpart in a bid to save water; some are planting succulents and cacti where the grass once was or opting to create intriguing zen-style rock-gardens. It has been dry enough and allotted irrigation water is in short enough supply that the drought-hardy plants--long-stalked succulents we have in the verge in front of our house--are starting to die off. The cacti in the back garden are starting to have problems too. You know it's bad when plants that start to re-grow from botanical cuttings if they're placed in a drying oven start looking poorly and/or dying.
So. Today, we'll be talking about the ever-lovely Golden Barrel Cactus (Echinocactus grusoni), first described by Hildmann (1891). I will admit that the barrel cactus has always been a favorite of mine. In retrospect, that is likely because it looks much like a cuddly pillow (unlike the soft-spined Paraguan and Brasilian native, (Notocactus leninghausii), but I digress.
Native to east-central Mexico, this particular cactus is colloquially known as both the "golden ball" and "the mother-in-law's cushion". It is also critically endangered in most of its endemic habitat (Querétaro, Mexico), though is often cultivated for ornamental landscaping and architectural accents. This popularity has unfortunately negatively contributed to population decline, due to illegal collection.
Each generation generally spans 30 years and by maturity, each plant has as many as 35 defined, spine-laden ribs, though these appear more as bumps on immature plants. The spines are long and either straight or slightly curved; they are generally yellowish, but sometimes also white. They are generally 4 ft tall and about 2.5 feet wide, though these measurements are highly variable. After about the twentieth year, small yellow flowers sprout from the cactus' crown in summer months. It grows wild at 4,600 ft / 1,400 m on volcanic hillsides. As they age, these cacti often become oblong, curving to the south or southwest (where the sun is strongest), allowing the spines to better protect the cactus' body from the sun. It is so pronounced that travelers have been known to use cacti positioning as a compass, rather like moss growing on the north-side of trees in the northern hemisphere.
3. Preston-Mafham, Rod & Ken (1992). Cacti: The Illustrated Dictionary. Blandford Press.
4. http://www.cactus-art.biz/schede/ECHINOCACTUS/Echinocactus_ grusonii/Echinocactus_grusonii/Echinocactus_grusonii.htm