I have been assaulted over my complaints of the dog poop that neighbors left and didnt pick up. Yes I mean literally shoved in the face and knocked down. I would walk out my front door and some dog has done his business on my freeking porch. Made me so damn mad. So next time this lady if you can even refer to her as a lady came by and her dog left poop, I waited until she walked off, go pick it up with surgical gloves,dump it right on her front door step. Thats how I got assaulted.
. Now here we are grown adults tossing dog poop around.
I dont know what the laws are there but if their is a foul odor thats obnoxious and obviously disgusting coming from your neighbors yard start calling and reporting a foul smell coming from your neighbors back yard that smells like a dead body. A few visits from the local constable might help. Its also a health hazard so you can call the health dept too. Start calling every official authority you can. Remind you they are your neighbor and you are going to have to deal with it.
Might go tell him his yard stinks and be nice to start with. I think of being nice as a last resort.
Its seriously a health hazard with all the flies and rats and no telling what else it produces. If they are a renter you can and should call the landlord or owner.
Dog poop is such a big problem in some large cities they actually have police that watch just for this and you will get a ticket for not picking up. We call them 'pooliceman'