Last evening while deer hunting, I heard a familiar alarm snort (blow) sound that deer make. I wasn't able to see the animal that made the sound. I know that there are feral hogs also on the property. Does the feral hog also make an alarm snort sound? If so, is it different from the deer alarm snort? How to tell the difference?

Yes, they will snort. It sounds a little different to me, maybe more of an high volume air flow sound with a little lower pitch and less whistle? Thats just subjective on a case by case basis though. Listen for a growl afterward or grunt sometimes also.

It really sucks when you are by yourself on a pitch black night and you hear the "growl" about 15 yards behind you.

I agree....but I love hunting by myself....everybody wants to go kill a hog but they don't have thermal and they just don't understand what it is like.....I would rather have someone with me but I love the spot and stalk across an open field to see how close you can get