Cleistocactus strausii
As a houseplant, the Silver Torch cactus is an easy to take care of so long as over-watering is avoided. To naturally simulate the porous effects of the sand in its native habitat, it's important to ensure that excess water will not pool in the soil, causing the roots to become water logged.
This plant’s native habitat does not have winter, but when temperatures drop to the low twenties, it can exhibit signs of tip frost. 
The Silver Torch cactus is most susceptible to 
mealybugs 
and spider mite.
San Andreas Creek
Fog drip may play a key role in the precipitation in the upper watershed. On Cahill Ridge (just west of San Mateo Creek and east of Pilarcitos Creek, at an elevation of , Oberlander measured fog drip beneath tanoak ("Lithocarpus densiflorus"), Coast redwood and three Douglas fir trees, the latter tall. He found that the trees most exposed produced the most precipitation and in five weeks of measurement (July 20 – August 28, 1951) fog drip below the tanoak produced of precipitation, more than the total annual precipitation on nearby grasslands and chaparral. The Douglas fir produced of fog drip and appeared to provide unique conditions supporting the orchids giant helleborine ("Epipactis gigantea") and phantom orchid ("Cephalanthera austiniae"), since these plants were found exclusively in these moist ridge tops.