turtle tree farm

function checkTree()
  turtle.select(1)
  if turtle.compare()==true then
    redstone.setOutput("left",true)
    sleep(3.5)
    redstone.setOutput("left",false)
    plantTree()
  end
end

function plantTree()
  turtle.select(2)
  turtle.turnRight()
  turtle.suck(4)
  turtle.turnLeft()
  turtle.forward()
  turtle.forward()
  turtle.turnLeft()
  turtle.digDown()
  turtle.down()
  turtle.dig()
  turtle.place()
  turtle.turnLeft()
  turtle.dig()
  turtle.forward()
  turtle.turnRight()
  turtle.dig()
  turtle.place()
  turtle.turnRight()
  turtle.place()
  turtle.up()
  turtle.placeDown()
  turtle.back()
end

while true do
  checkTree()
end