THe concept of “stand your ground” is probably irrelevant here since there was “no ground” to “stand” re Zimmerman or Martin.
Zimmerman wasn’t protecting his “ground” (i.e. home, yard, car) and neither was Martin. He was patrolling it as the eyes and ears of his neighborhood. When he called the police, he was doing what he was supposed to do.
Martin was moving, so where is “the ground” he was protecting? None, and if he moved on Zimmerman, there was still no ground involved. If Martin had been at his mother’s house, then you would have had a different scenario.
This is a real red herring for lawyers to spout off on, like a bull with diarrhea, but in the end, it means nothing (except for the poor bull).
That's true because the fact pattern in this case negates the possibility of escape. In he general case, Florida's absence of duty to retreat extends to anyplace one may lawfully be.
Actually ... he wasn't patrolling, he stated elsewhere that he was on an errand to the store when he saw Trayvon casing a house.
Zimmerman admitted carrying his piece on patrol (that's the end of his involvement in Citizens on Patrol, very probably, since it's against the rules), but at the time of the incident he wasn't on patrol and so wasn't breaking any rules.
By shooting Trayvon, Zimmerman proved that a) Trayvon was a criminal and Zimmerman had correctly profiled him, b) it endangers Citizens on Patrol volunteers to demand that they go on patrol without any sort of weapons, and c) the dangers increase when patrollers dismount, against the rules as Zimmerman did (if he'd been on patrol) -- but then the rules confine the patrollers to the point of uselessness in a scenario like this, involving a home invader/house burglar who is trying to avoid contact with police.