Moss in grass is a bad sign

If you were a cornerback in the NFL seeing Randy Moss lineup across from you was a bad sign.

Moss in grass

Moss is a bad sign in grass as well.

Moss in grass

Moss in grass

Shade and grass

North sides of house are sometimes hard spots to get healthy grass to grow. Those areas are in the shade far longer than other parts of the yard making it easier for moss to grow. You may have to get creative with your watering to allow those areas to dry out. In a perfect world these micro climate areas would be on their own sprinkler zone, so you can alter the water on that specific zone, without altering places in the yard that receive a lot of sun. If the grass is in constant shade it will be difficult to get grass to grow regardless, and it might be best to put in a rock bed.