I had a huge African poplar tree in front of my house. I cut it down and cut the stump down to just under ground level and covered it with top soil. The following spring there was poplar shoots everywhere. They were in neighbours gardens up to 100yrds in every direction. You must deal with the roots not just the stump. The stump is the quick and easy part!
If you have any more poplar trees the correct method woud be to use a systemic herbicide apply to the fresh cut stump allow a few weeks for the herbicide to reach all the root system then use the stumpgrinder to remove core of the stump and visable roots so no need to treat the machine like a excavator!
Or you could possibly put a piece of plastic over the stump that you just removed cover the plastic with dirt hopefully I'll stop it from photosynthesizing
When grinding stumps is it hard to go over the mouth on low gear I just got a new machine that’s a wheeled and I’m wishing I Would’ve got the tracks until