Computercraft - Auto Birch Wood Farmer Code

31 lines (24 with data), 478 Bytes

term.clear()
term.setCursorPos(1,1)
print("X90 Tree Farmer")

doWidth = 5
doLenght = 5

  for i=1, doLenght do

if turtle.getFuelLevel() < 10 then
  turtle.select(15)
  turtle.refuel()
end
    while not turtle.detect() do
    turtle.forward()    
    end

        turtle.dig()
        turtle.forward()
    
    while turtle.detectUp() do
    turtle.digUp()
    turtle.up()
    end
    
    turtle.select(16)
    while not turtle.compareDown() do
    turtle.down()
    end
  end