Yamadori hawthorn

I was fortunate to have access to a forest near to where I live, I decided to go in search of some decent sized hawthorn .
I found two with a good 6 or 7” girth (I’m a relative beginner) with the forest floor being so fertile they came up with ease so I removed the tops dug them up and took them home and planted them in large training boxes,this was about 4 weeks ago and therewas a few buds left on .
After further research I found I should of dug around and left the plant for a year, these had few or no fibrous roots , however the buds have developed into leaves , is this the tree living off the remaining sap or are they going to survive .
Any advice would be greatly appreciated.