Botanical_Bryce

I've used regular castor oil just fine but if you need you can get the thick sticky stuff at farm and feed as a repellent that goes on the hose. There are also mole and gopher repellents already with it in. Just read the ingredients to be sure. For wood panel fence i would concrete all the posts. I have seen them with only some concreted. Only the top layer of sand should be loose. Even in the extreme sandhills that is how it is. Remove the loose layer with a shovel then use the post hole digger or auger.