Need to make a dog poop zone outside- suggestions on material?

Most prefer grass, but failing that I'd go with pea gravel--it's easier to keep clean, straw is not easy to scoop the poop from, wood chips are toxic to dogs, leaves, again, to hard to clean.
My dogs are trained to poop in the bush that borders our yard but it's actuall fairly easy to train them provided you put in a lot of work for the first 2 weeks.
Basically, every time they go out, you take them to that spot and wait with them to go, praise like crazy and repeat. To start them out it's handy to put some poop from other places in the yard in the area you want them to go.

Oh, I forgot to say thanks so much for that bit of info on woodchips. I had absolutely no clue that woodchips were toxic to dogs. Can you tell me why this is? Is it the chemicals that are likely in most?

Sorry, it's not a bush like a shrub, it's a wooded area between our property and the next one--although, I admit, Havoc does like to poop on an old tree stump
It is the chemicals in the chips that are toxic.

I have to disagree on the pea gravel. It is cheap & non toxic, but it is not all that easy to clean up poop off of. I end up putting a lot of gravel in the garbage! It's not my favorite substance.

use a hose to clean the poop off the gravel after you've picked up the worst of it, I have up to 10 dogs a day pooping on pea gravel and I only add new once a year. You do need a good thick base though. I prefer 3/4 inch limestone as it also keeps the odor away but a lot of dogs don't like to walk on it.

Hmmm... I'll have to look into the pea gravel. I hadn't thought of that.

Shannon and anyone else who's done this- basically how do I do this? Bring them to the spot on a leash, tell them to go, then act crazy happy and give them a treat when they go? One of them is clicker trained and although I don't use it much anymore, i wonder if she would respond well to using the clicker.

Thanks!

yep, that's about it! and always make sure there's at least one poop sitting in the area you want.