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Cutworms

© Carla Goodloe

Cutworms range throughout North America.

Adults are brown or gray night-flying moths with a wingspan of about 1 and a half inches. Larvae are fat, gray or dull brown and about an inch and a half long with shiny heads. They curl up while at rest or when disturbed. Kind of like a grub only not white.

The adult moths of black and variegated cutworms are blown North each spring by winds. Their grandchildren are blown back down South in the fall by cold fronts. Other types, including claybacked and darksided cutworms, overwinter int he North as eggs. Eggs hatch into larvae in about a week. Larvae grow and feed for about one month, then pupate in the soil. Adults emerge in about 10 days, with females laying eggs on plants on their fifth night.

Their food supply includes flower, grain, weed and vegetable seedlings.

The cutworm larvae chew off tender shoots at ground level, feeding at night and staying underground during the day. Some cutworm larvae stay below ground all the time, feeding on buried portions of plants. They tend to cut off seedlings just above the ground and eat the dropped portions leaving a stub to let you know there were there. This can be very devastating to a gardener and replanting will be necessary. So have a few extra seedlings around just in case otherwise you'll get a late start in the garden.

Predators and parasites are good controls. Some include toads and ground beetles which feed on the larvae at night. Nematodes and tachinid flies parasitze the larvae.

Other controls include removing weeds and plant debris from your garden before planting to starve developing larvae. Bt, a natural and organic pest control mixed with bran and molasses and sprinkled over the soil before planting will kill larvae. Protect stems of transplants with collars of cardboard or metal, especially when planting into ground that was previously sod or pasture. Claybacked and darksided cutworms can become serious pests where sod is replaced with crops. Handpicking after dark is tedious, but for small gardens is very effective.