Watered down vinager water in a spray bottle worked for me.

That's sounds like a good idea, PJ. I used to raise and show Basenjis and when you have a kennel of dogs there's going to be a few dog fights. The only thing that would break them up was scented room spray. It doesn't hurt them and they hate the strong odor so a whiff of that everytime they bark might make them decide it's not such a good idea.

If dogs are going to bark at you not even a board fence they can't see through will stop it, so I doubt that a hedge would do so.

Roselee is right. I have dogs next door that can't see me through the privacy fence, but they still bark at me. They don't scare me though. My dog is a rottweiler and they are little yippy dogs. My dog thinks they look delicious!

Air freshener lol! That's a new one! "Blech mom that STINKS!!!" (Lets stop bickering and go roll in something dead to get the smell off!!)

Rattling a can of rocks also works. Apparently they hate the sound and move away from the fence. You have to keep at it, but eventually they quit barking altogether. It's worked twice with neighbor's dogs over the years. One time this method caused the dog to start barking at the neighbors on the other side.

PJ -- that's about it ... hahaha!

Hadn't heard of the can of rocks trick. It's sure worth a try.

I've read about some kind of amplifer that will play the dog's barking back at them. Maybe that's sorta' of what they get with the rattling of the can of rocks.

A friend told me about the can of rocks method and I think she learned it in a dog training class. I looked it up and the info is for training your own dog, but I know it works because we've used it.

It's item #6 in the list. We didn't reward the neighbor's dog with treats of course and just kept shaking the can until he gave up. Sometimes we rattled the fence with a stick at the same time and he definitely didn't like that. He barked around the clock, it was really awful. The owners apparently felt safer that way. I have my doubts because one day we had a satellite TV guy go up on the roof without our knowledge and not a peep from the dog even though it was on his side of the yard.

Here is a link that might be useful: How to stop dog barking

Barberry would make a good thick hedge (not the dwarf type). These are taking the drought/heat very well too, just some slight burning on the tips. I would be hesitant to grow anything fast growing as you might regret it down the road with the frequent trimming. The Mountain Laurel would be a good choice as well as some of the newer types of landscape roses, the large everblooming shrub types. Maybe a mixed planting. The landscape roses look very good planted among large Miscanthus grasses and deep green evergreen shrubs. I have seen these thickly planted together and its very nice.

The unselected types of Cenzio (Leucophyllum fructescens) will reach 8ft.

or, on a more offensive note:
Ocotilla is used for living fences if you can find the branches. I don't think a dog would come through that or some of the large padded prickly pear cactus with a few imbricata tree types here and there.

Read about trifoliate orange. I think it would keep anything out except maybe snakes.