This goes further afield from the main issue, but when someone is without a clue, a golf idiom that works well is “like a lost ball in high weeds.” (I’ve been known to use that one away from the golf course, too.)
Wasington, Colorado & Georgia–never heard of the plural form. “Bush” is typically some kind of wildernes. Bush"es" refers to a specific (by context) patch of overgrowth.
“I lost my rifle somewhere in the bush”
“Dang, tough luck bro.”
“I lost my rifle somewhere in the bushes.”
“Well let’s go find it. Which bushes? Shouldn’t take long”
As for me, I lost my virginity in the bush. 
Now that you mention it, it does sound like a golfing metaphor.
Although I have heard and used the term (or the variant “in the bush”), more commonly I hear and use variants like “sticks”, “boonies”, “boondocks”, and “weeds”. Also, I wouldn’t use it for small towns, but rather for rural areas, like someone who lives on a low population country road, or at most, a small collection of houses and stores at a crossroads that’s otherwise in the middle of nowhere.
But that’s mainly because I grew up living in the sticks outside a <20k bush-league town. 
Nope, never heard it. The closest would be “out in the bush”, but I’ve always understood that to refer to outright wilderness, not small towns.
Another vote for “out in the sticks” or “out in the boonies”. But I’ve never heard “out in the bushes” except to describe something that was literally in a bush.
I say “outer fucking boonie land.”
An elderly friend of mine (God rest him) used to say, “out where Christ lost his shoes.”
I was always told that one in the hand was worth two in the bush, but given your context that equation seems at least backwards.
Sticks, boonies, boofoo, boofoo Egypt, BF Egypt, BFE, buttfuck nowhere, buttfuck Egypt, bumblefuck are the expressions I’m familiar with. Never heard of “out in the bushes.”
The only people I’d expect to find out in the bushes are Peeping Toms.
I’ve heard “in the sticks”, “in the boondocks”, “in the boonies” and some more specifically Australian ones like “the back of beyond”, “beyond the black stump”, and “the arse end of nowhere” (or “the arse end of the world”).
Never heard that. We say ‘the boonies’, ‘the wop wops’ or ‘back of beyond’.
The small villages in rural alaska are refered to as “The Bush.”. As in, “he’s flying out to The Bush tonight.”
Just thought of a couple expressions/sayings that mostly fit the theme:
- Plumnelly – plum out of town and nelly out of the world
- It’s not the end of the world but you can see that from there
In Australia we use the bush to mean rural areas. For really remote areas we’d say the sticks, the boondocks/boonies, the back blocks, or the more old-fashioned beyond the black stump or back’a’bourke. I’ve never heard of “out in the bushes” being used in that kind of context.
Heading “out bush” or “out to the sticks” is common where I am in Australia. Going “in the bushes” is what you do when you want some privacy for certain bodily functions. 
On Car Talk they call that “needing an urgent haircut.”
Another vote for “sticks.” Never heard “bushes.”
Never heard of “bushes” but would have guessed it came from baseball. I’ve always heard “sticks” or “boonies,” but that’s really for sparsely populated rural areas. For small towns, I think I’ve always used “Podunk” or “Bumfuck.”
I’m another one that has always heard “sticks.”
I’m a little surprised that nobody has mentioned one of the most famous headlines in history–
“Sticks Nix Hick Pix”
“The toolies” or “East Jesus” for me.