The second time in a week. Using a bushhog for land cleaning attached to a compact 25 HP tractor. I knocking down with it the biggest saplings that it can handle forcing it backwards between the trees. 5PM pulling it back until my drive and the little 60 inch bushhog snags having become disconnected from the 3 pt hitch. I see a retaining pin has fallen off. The type of pin that has a tension ring that keeps the three pt hitch arm from sliding off. I had another and once I figured it out had the 3 pt hitch reconnected. Fortunately with my bad back I was able to lift a bit and not hurt myself.