How to Grow an Apple Orchard?

Trees are very expensive to buy at you yer sensly. If i, if i got a acre of trees that are sort of past their prime, i can go out and stick the new, hot variety in there. And i graft it. I use the roots that are already established. The cambiun layer is essentially outer half inch of the of the tree. That's were all the zilum and flo and all the sugars go up and down. It seems different to me. Apples are just these happy little trees. They don't need all this fertilizer and all this stuff, do they?