The word of the day is stanchion:

estanchon, estançon (modern French étançon), < estance prop < popular Latin *stantia: see stance n.²... 

An upright bar, stay, prop or support.  (OED)

"end of the day daylight subsiding into the trees lights coming on

in the milking barns as somewhere out in the yard some ants

are tucking in their aphids for the night behind

hydrangea leaves or in their stanchions underground

they have been bred for it the smaller brain"

 - Ellen Bryant Voigt, "Cow", 6 December 2010 The New Yorker