First, let me be clear, I absolutely detest killing trees! And I love mulberries!
Unfortunately, I had one I cherished, and actually fought quite hard to keep alive, that ended up riddled with nectria fungus, which I read was fatal and untreatable once it's on the tree's trunk, not to mention contagious to any nearby plant (and this was in a food forest, so lots of things were nearby).
With a heavy heart and a hand saw, I cut my mulberry down, bagged the debris, and washed all of my tools and gloves. But, as is routine for mulberries, immediately new branches sprang up from the root system. I keep cutting them down, and more pop up. I have covered it with cardboard and large rocks, but more fungus-laden branches keep finding their ways out. I can't get to the root system without potentially harming other nearby plants and making them more susceptible to the nectria spores in the area.
How do I convince this sad little mulberry that its time has come?