How much compost for seedlings and large fruit trees

Found a video where a professor used only a coffee can's worth of finished compost for a raised bed maybe 12ft by 12 ft.  It looked very sparse.
This got me thinking.  I am currently making huge piles of compost (hot composting) in order to start a small orchard.  Made with wood chips and spent beer grain from a local brewer.
I will soon get an order of Pawpaw seedlings and Persimmon seedlings for planting in the ground and some will go into tall tree pots.
I have already covered the ground with wood chips.

After planting the seedlings, how much compost should I put around each one?  I also have some mature trees and how much should I put around those?

I will usually use compost as a mulch of 2-3 inches around my fruit trees. I go out to the drip-line. I add another 2-3 inches when it has broken down into the soil, maybe twice a year.
Do not dig it into the soil, just add it as a mulch. Fruiting trees have many surface roots.