By Jill Vance, Interpretive Naturalist, Spring Mill State Park
If someone asked you to describe a snail in one word, what word would you use? How about slimy? Snails are known for the silvery trails of slime they leave on soil and plant leaves. This slime helps them in many ways.
Snails have a long, moist, and, of course, slimy body. They are gastropods; “gastro” means stomach and “pod” means foot. The mouth of a snail is located on one end of its “foot” (the body of a snail). Slime is produced by a special gland in the front of the snail’s foot.
Because the sun can dry out their soft bodies, land snails are active only at night or on cloudy days. The rest of the time, they hide in moist, shady places. During the winter, they hibernate in the soil.
Slime provides snails with additional protection during dry weather. They can pull their body inside their hard shell and then seal the entrance with slime to keep moist. Some desert snails have thick shells that allow them to stay sealed inside their shells for more than two years!
Snails can also use slime to help them get around. As their foot produces slime, it also ripples (like a wave); this movement pumps the slime backward, which pushes the body forwards. While this type of movement is slow (about 2 feet per hour), it does have advantages.
Using the slime, snails create suction between their body and a surface. This allows them to stay connected at all times with the surface, so they can easily crawl across a ceiling or, more likely, the underside of a leaf. The slime also creates a protective layer under the body. Snails can move across rough vines, harsh soils, and even the edge of a razor without injury.
Snails are fascinating creatures. The next time you spot a snail, take some time to watch as it propels itself, slowly, along its trail of slime…
Many gardeners watch their gardens for the silvery slime trails that snails leave behind; snails eat leaves and can damage garden plants. But while the average snail can be a pest to gardeners, the giant African land snail is a major threat. It eats more than 500 kinds of plants and can carry diseases. This enormous snail (up to 8 inches long!) does not belong in Indiana and was brought to the United States illegally in 1966. If you see an African land snail, report it to the Indiana Department of Natural Resources, Division of Entomology and Plant Pathology, at (317) 232-4120.