TNBarnQueen, A corgi is the smallest of the herding dogs and also the only dwarf dog. They were developed to herd geese, sheep, bulls,ect..which explains all the attitude. the collar sounds like my best bet, it may also help with her desire to bite Zeus ( our Golden retriever).
I found a great FREE resouce today. our next door's were having a tree trimmed/topped and had about a 1/8 of a huge dump truck of mulch, they drove it over to my house and dumped as close to the barn as they could get. Seems all the tree places are ALWAYS looking for places to put the mulched up bits. So if anyone else would like some for their run call a tree service and talk to them--be sure to tell them what trees you cannot have, cherry, peach, black locust, oak and in my case black walnut ( all apply to my donkey as well). Also, if you don't have as much space to have a dump truck come onto your land--you can spread a tarp and have them dump there--just be sure that's where you want it or you have a wheel barrow or pull behind trailer to move it.