TreeFarm

function getMeal()
    turtle.turnRight()
    turtle.select(3)
    turtle.suck()
    turtle.turnLeft()
end

function deposit()
    sap = turtle.getItemCount(1) - 2
    wood = turtle.getItemCount(2) - 1

    turtle.turnLeft()
    turtle.turnLeft()
    turtle.select(2)
    turtle.drop(sap)
    turtle.select(1)
    turtle.drop(wood)
    turtle.turnRight()
    turtle.turnRight()
end

function breakTree()
    while turtle.detectUp() do
        turtle.digUp()
        turtle.up()
    end

    while not turtle.detectDown() do
        turtle.down()
    end
end

while turtle.getFuelLevel() > 100 do

    if turtle.getItemCount(3) == 1 then
        break
    end

    turtle.select(1)
    turtle.place()
    turtle.select(3)
    turtle.place()
    turtle.dig()
    turtle.forward()
    breakTree()
    turtle.back()
    os.sleep(120)
    turtle.suck()
    turtle.up()
    deposit()

    if turtle.getItemCount(3) == 1 then
        getMeal()
    end

    turtle.down()

end