Voracious eaters, they slide along on a muscular foot, eating plants and creating slimy mucus as they go. One visible difference between these closely related pests is that snails have hard, protective, external shells. Some slugs have soft internal shells or prominent mantles, while others have nothing at all. Both slugs and snails have two upper tentacles that protrude from their foreheads.
Used for sight and smell, they carry eyes on the tips. Shorter, lower tentacles extending down from their heads are used for touch and taste. Slug and snail populations are highest in warm, moist, humid climates. In the United States, the Pacific and Atlantic coastal areas are prime regions for slugs and snails, with the Pacific Northwest, tropical and subtropical Hawaii, and Florida especially hard hit. But even gardeners in cooler, northern climates are threatened by these pests.
From Maine to Minnesota, slugs and snails simply wait out winters in hiding spots that protect them from freezing. Snails' protective shells also influence their location. To form shells properly, snails need calcium, which wild snails get primarily from soil. This need limits their range to areas where natural soil and weather conditions combine to keep soil calcium readily available.
Their shells help them tolerate these often drier climates, too. Shell-less, unprotected slugs don't need calcium like snails do; they need moisture. They flourish where it stays plentiful. Many slug and snail pests that damage U. Non-native species have been brought into the country over the years — intentionally and unintentionally— adapting nicely and finding coastal U. The aptly named taildropper slugs, such as the reticulated taildropper , can quickly amputate their own tails.
And certain sea slugs have body parts that snap off safely and easily, leaving a would-be predator with a smaller, less desirable meal.
This position enables them to extend their gigantic, body-length penises and wrap them around each other. Another sea slug sets the mood by stabbing its partner in the head. But that goo is pretty remarkable. It can be both adhesive and lubricating, and it actually slurps up water.
Why all the goo? Slug slime is multi-purpose. It helps these critters move and climb challenging surfaces. It also protects them from fungi and bacteria.
Plus, slugs can learn about each other—and find potential mates —by examining slime trails. Some land-living slugs can get pretty large. They destroy young seedlings and chew holes in hosta foliage, leaving them unattractive the entire season. Slugs bury themselves in the soil or find a moist, well-protected spot where they remain in a state of suspended animation. They secrete a mucous-like cocoon around themselves and wait it out until there is enough rain or moisture to dissolve the mucous and soak the water into their bodies.
They can loose as much as 50 percent of their weight during a dry spell and then regain it all after only two hours of rehydrating. Slug damage is often as serious in late summer as it is in the spring due to renewed soil moisture levels and higher populations. Slugs secrete a slimy mucous trail as they move across plants and smooth objects. This prevents them from drying out and provides a protective track on which they glide across sharp surfaces.
It can be seen as a silvery trail on leaves. Cultural Control. One tactic is to reduce the favorable habitats where slugs live and reproduce. Keep mulch layers shallow; a uniform, one-inch layer will prevent rapid drying around the plants and will not retain excessive soil moisture. Since slugs also feed on decaying plant material, do not mulch with fresh grass clippings where slugs are a problem, and rake leaves from the garden beds in the fall.
Mechanical Control. Traps are a mechanical form of slug control. Picking slugs by hand is probably the least environmentally damaging method of eradication.
Arm yourself with a pointy stick, skewer, barbeque fork, or chopsticks and a jar of soapy water. Early morning is the best time to catch the beasties out, although nighttime hunting with a head-lamp can be rewarding. Search under boards and stepping stones and other dark, moist hiding places. Simply skewer or tweeze the slugs up and drop into the soapy water. I like to skip the soapy water and dump the jar of slugs into my chicken pen. Ducks also love to gobble up slugs. Beer traps are another environmentally friendly way to put a dent in the slug population.
Half fill a plastic cottage cheese or margarine container with stale beer or this mixture. Cut half-circle openings in the rim of the container and snap the lid back on. Place the containers near tasty plants in the garden. Slugs will crawl into the container and drown. The barb contains a paralyzing toxin that keeps the prey, usually a fish, from swimming away.
The up side to snail venom: scientists are now researching the use of cone snail poisons in treatment of neurological diseases such as epilepsy. Hmmm…probably not a great idea.
Snails and slugs can harbor bacteria and parasites that cause diseases in humans, including Angiostrongylus also called rat lung worm — yuck!
If you must eat a slug, thorough cooking and hand washing will minimize disease risks.
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