I've always seen them used by landscapers and horticulturalists. Your mention of orchards makes sense too, although I've never seen them spiked into the ground. I think they're just for any place not level enough for a regular 4-legger.
Grew up on a fruit farm using that type ladder in the orchards.
Yeah. I have a couple of wood 4 leg ladders for building maintenance. That seems a lot safer for anything near electricity as well as avoiding that inevitable leg-slip.
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The decal inside one leg, says a strap is mandatory for firm ground or a hard surface. But I've never seen a strap used.
That probably depends on the brand. On mine the hinge at the top limits the opening. Mine are aluminum and I never use them on hard surfaces.
Interesting. No limit on mine. it's not unusual to lift the front leg high and put it through a crotch in a dense apple tree then plant it on the far side, to get in close and harvest the center of the tree.
Back in my school days, they were still teaching us how to hard-wire those old IBM Accounting machines. They had vertical type bars with alpha, numeric and symbol segments which were hit with hammers. It was actually fun to watch all those bars going up and down independently as it printed one line at a time. As I recall, it took about 5 minutes to print a page of green bar. They had memory listed in characters--Typically, 1400 so you couldn't add up very many columns. They were as noisy as a metal shredder.
By late 1991 made the mistake of demonstrating competence at Unix, in the midst of my employer’s DoD contracts getting re-written by the government (apparently they can do that) and I was transfered from an engineering development and analysis position to a well funded contract as a security officer and system administrator. Had $4M of state of the art SGI machines. 12 machines, 9 with the GT graphics hardware.