It is a very difficult thing to fix....Depends on why it started too
Some puppies learn from their mom's, it is really difficult to fix. Picking up as soon as might break the habit....
Pineapple is supposed to help
Some dogs it is diet related, they are missing something in their diet. One of our local vets really believes giving a teaspoon of kelp might eventually help, but you will still have to pick-up to get out of the habit.
Telling them off will not work, because all they will do is do it whilst you are not looking, just like with potty training.
I think a combo of all might help....Also maybe initially doing the potty on lead, really praising and quickly getting rid of the offending matter.
If it is horse/deer/cow poop, I would not worry. A great way to get digested veggies and get some excitement out of you when they give you a big kiss after eating it.
It will be a tough road to travel.........