function TreeTop()
  turtle.dig()
  turtle.forward()
  while turtle.detectUp() do
    turtle.digUp()
    turtle.up()
  end
end --TreeTop

function TreeBot()
    while not turtle.detectDown() do
      turtle.down()
    end
    turtle.select(1)
    if not turtle.compareDown() then
      turtle.digDown()
      turtle.down()
    end
end --TreeBot()

function Harvest()
  TreeTop()
  TreeBot()
  TreeTop()
  TreeBot()
  turtle.turnRight()
  TreeTop()
  TreeBot()
  turtle.turnRight()
  TreeTop()
  TreeBot()
  turtle.turnRight()
  turtle.dig()
  turtle.forward()
  turtle.turnRight()
  turtle.back()
end --Harvest

function DumpInventory()
  turtle.turnRight()
  turtle.forward()
  turtle.forward()
  for i=2,16,1 do
    turtle.select(i)
    turtle.drop()
  end
  turtle.back()
  turtle.back()
  turtle.turnLeft()
  turtle.select(1)
end --DumpInventory()

function Main()
  while true do
    if turtle.getFuelLevel() > 500 then
      Harvest()
      DumpInventory()
    end
    sleep(10)
    n = turtle.getFuelLevel()
    print(n)
  end
end --Main

Main()