My partner used to work for these folks, he'd say you were getting paid 9-13 cents to bend over. Folks making $200-350/day planting 2000-4000 trees each, with camps 60-100 people; summit runs multiple camps. It's quite the lifestyle, some planting camps are a bit of a wild place.
Where I planted, The ground was often rocky so it was tricky to close the holes properly after planting a tree. It's also very important not to bend the tree roots. It would be very difficult to accomplish that reliably without bending over. As far as specialized tools, generally from what I have seen the spade is sharpened and one half is usually ground completely off
