G'day
Large cacti plants similar to those are very common here in the west as well, found a lot around the old goldfields towns and often seen along many country roadsides, I always associated them with where an old house or building may have stood in the early years, for that matter any type of tree or shrub that I see off the road that is not native to here is a good indicator of some sort of structure being there many years ago, also I often see tall palm tress and also as mentioned peppercorn trees as well, interesting to know that the cobb and co coach stops were about ten miles apart, as I know where there is a plinth off the side of the road that states that a cobb and co coach stop once stood on that spot so I will look for likely spots further along that road as well.
I have tried to find out what those cacti were used for and have heard many stories, they must have had quite a few uses as they are very common, I have heard of the beer and alcohol brewing, also for medicinal use, and also that they were planted outside windows mainly to stop people easily climbing in as they are pretty vicious, back in the day robbery was common and they still had issues with the wild aborigines so I would think that if you wanted to be able to leave a window open on a hot night so you could get some sleep, anyone who tried to climb through the cactus to get in the window would have to be very tough to get through them without waking you up in the process.
https://www.bushlandperth.org.au/weeds/century-plant/
cheers
stayyerAU
