Unique individual fruit and nut trees exist in nature due to fertilization, which requires unique genetic information (DNA) from two individuals. If you are looking for an individual with identical characteristics as its parent in terms of fruit size, quantity and drop time then these plants must be grafted or produced by tissue culture techniques. Fruit trees are relatively easy to graft. Oak trees and other hardwoods are much more difficult to graft and require extra time and expertise to reliably replicate an individual tree. If you understand this basic genetic fact then you will be able to see through deceptive marketing found on some of the larger websites with plant material for sale for wildlife applications.