Not very much. Their arms are tiny. Average weight of woodchuck is 3.9kg. if we look at a human (agile, long arms comparitively), and perhaps use the weight of a hammer (like from hammer throw competition), which is 16kg, and AVG human weight in hammer throw… maybe 90kg? That’s gets us 17.7% of weight. Transfer to groundhogs that’s about 700g, BUT their short arms surely like t this a lot. I’ll say at least by 75%. Which leads to: 175g. A woodchuck could chuck 175g, if a woodchuck could chuck wood