[&:] 50 lbs of 10-10-10 will kill the biggest oak you can imagine!!!!

Take a pitchfork, poke holes even with the canopy....no more than a pint per tree....[&:] You do NOT want to burn the roots that are NOT used to heavy fertilization.... We have some 36" diameter white oaks here.... They get a small handfull every other year!! The leftover acorns from a "bumper crop" act as the fertilizer in mast crop years.

You might want to contact your local forester for advice.....[]