http://www.vegetariat.com/2015/02/compost-gophers/ This is a wonderful blog about discouraging Gophers without toxins. I have gone the same route, but I deliberately let my food scraps ferment for a week or so. I fill a 5 gallon bucket half full of table scraps, put in enough water to just begin to see liquid below the top veggies, and then put a second 5 gallon bucket on top with sometimes a little weight. In a week there is plenty of liquid from the breakdown of the scraps, whereupon I take a paint stirrer that I put some edges on with a grinder and puree it. A little extra water if needed and …
Old bread works great as in the picture.
I then pour it through an old milk crate into a tub and from the tub back into the bucket. This screens out large pieces that would plug the hole rather than flow into it.
Now pour it down the holes.
I am exceedingly happy with the results. And as the original blog post points out, I am fertilizing at the same time as discouraging the Gophers from digging in certain areas. I am perfectly happy to let the Gophers have other areas of the property. Just not underneath the trees :-)