Nice method, but I prefer just keeping my distance and looping them around small weeds. They get stuck trying to headbutt you and you can give em a good 2-3 hits before they attack again. So just keep hiding behind those weeds and you should be good took me about 2 minutes with a pebble axe.
Since I play on the hardest difficulty I found that the hammer works but still similar situation where I'm only able to take a few shots. Recently, as I progressed, I did find a weapon that is made out of mint that is a club proving a busting effect. I will need to check what it's called but it provides fresh and you can take out a ladybug really easy once you put a few upgrades on it.