Take out feeders before pushing. I usually drop fel bucket abou 3 or 4' from tree and dig up feeder roots, dump dirt , raise bucket 5 or 6' and push tree over all in one stroke. Height I push on tree depends on size as smaller ones will break. Larger/stubborn trees take more feeder removal and pushing. Often the taproot breaks off below ground level. This works on a lot of trees up to 8-10", but gums are really limber and have the thick tap. Ive dug all around them as in above pic and tried to push them over, but they just bend over. Frustrating.