A nursery/landscaping company planted two trees (Accolade Elm and Green Mountain Sugar Maple) on my property as part of a city project.

I made sure to speak to the crew prior to the planting about the importance of making sure the beginning of the root flare is above grade.

Much to my chagrin, I arrived home in the evening to see that the root flares were not visible on either tree. I did some light digging and found that the flare was 2-4 inches below grade depending on which side of the trunk I was measuring from.

Based on the attached photo, am I correct in asserting that the trees are planted too deep?

If so, and the contractor refuses to remedy the situation, is it in my interest to have a tree service come out and attempt to replant?

I could expose the root flare and leave the tree at the current depth, but my concern is that water would pool in the depression. Could I fill the depression with pea gravel? Would the flare eventually fill the depression? Is there another option I'm overlooking?

Above all, I just want to make sure these trees are given an opportunity to thrive.

Any input/advice is appreciated.