Army Worm
During the stage of a caterpillar, white/gray/brown moths are known as armyworms. It is wise to be aware of these worms if you grow vegetables and herbs in your garden. I highly recommend handpicking armyworms. However, it is too exhausting and time-consuming.
Cut Worm
In addition to eating grass near the soil, cutworms cut it off. Most of the damage is done during the first few weeks of the gardening season when they emerge and feed on the seedlings. Plant roots and leaves are their primary food sources, and they will even cut off plants from underground. They destroy whole plants in most cases; they do a lot of damage very quickly.
Sod Webworm
As with cutworms and armyworms, these greenish-grey larvae/caterpillars have black spots along their bodies. Leaf undersides are the food source for these worms. Small, ragged holes first appear as brown spots on the turf. The dead areas continue to grow as they feed, and may join other areas of large dead grass. It is caused by direct sunlight and is most prevalent on slopes that are south-facing or surrounded by bluegrass, bentgrass, tall and fine-leaf fescues, and buffalo grass.