Difference Between Grubs & Maggots

Grubs and maggots look almost identical when they are in their worm form. But when they grow up, they turn into different insects -- the grub turns into a beetle and the maggot turns into a fly. Although they are noticeably different when they are flying insects, differences exist when they are worms as well.

The life cycle of a maggot is extremely fast, while grubs take a little longer to mature. In both species, the eggs from the female are laid in moist soil or mulch. The eggs of a maggot take anywhere from eight to 20 hours to hatch, while grubs take up to two weeks. The grubs and maggots begin to feed as soon as they hatch until they transform to a different stage. It takes almost a whole year for a grub to complete its transformation into a beetle. A maggot, however, can complete its transformation to a fly in as little as a week.

While maggots are used for medicinal purposes, grubs are not. Grubs are hated because they eat through moist soil, causing damage to lawns. Maggots, on the other hand, stick to eating parts of animals or rotted vegetation. Scientists and doctors use maggots to clean wounds if conventional methods are not enough to heal infected burns or ulcers. The maggots eat dead tissue surrounding the wound and kill bacteria.

Besides eating away at expensive turfs and lawns, grubs are not known to cause any major diseases. Maggots, however, have caused diseases by chewing away at the insides of animals and humans. Myiasis, an infection caused by maggots, occurs when a fly uses an animal as its breeding ground. The maggots hatch and begin eating away at the animal. Internal myiasis can also occur if an animal or human ingests something that contains larvae eggs. If using maggots to treat an infected skin wound, make sure you are under a professional's supervision.

Maggots and grubs also differ in size. Maggots are a small, creamy white worm, often reaching only a half an inch in length. They are small and legless, and must crawl from place to place. Grubs are a bit longer. Some grub species can reach over an inch in length and have legs to scurry underground through soil. Grubs are usually off-white with a brown head.