Power to the outbuildings
The 3 aught is needed for the whole distance. Running thinner wire halfway will necessitate much much thicker wire for the second half in order to keep the total voltage drop within acceptable limits. Including the wires from the subpanel to the receptacles the total voltage drop should not be more than 4%. While peak load is seldom sustained, motors draw the most current at startup and significant voltage drop at that moment will cause degraded operation.
The disadvantages of crab apple trees. In summer, the apples are too sour to pick and eat. In winter the birds come and leave dropping all over the place.