The Waterman and Hill-Traveller's Companion, a Natural Events Almanac
About the book
Natural Events

< <   |   > >
Smallmouth Salamanders
Sulphur Butterflies
Chorus Frogs
< <   |   > >

Search this site
Site Map

Contact us
Photo by Jim Jung. All rights reserved.

17 - Slugs Lay First Eggs

I like slugs. I freely admit it and over the years I've come to accept that this isn't a flaw in my character, though others might disagree.

Slugs are molluscs, an ancient group of animals that includes chitons, oysters, scallops, nautiloids and octopuses. Unlike nearly all molluscs however slugs have discarded their shells leaving the water behind and moved onto land where, as any gardener will tell you, they're very successful herbivores.

But while they've left their watery cradle they're still extremely dependent on it. Lacking limbs they move about by exuding a layer of slime secreted by special glands on their "foot". Slugs are about 97% water and have been described as bags of cold water that have to leak to move around. (Not my first design choice for land travel but then I wasn't consulted.) As a result slugs are confined to permanently damp shelters during daytime and usually travel and feed only at night when higher humidity and cooler temperatures minimize water loss.

Slugs can reach impressive sizes six inch specimens are large but not unusual. They're also territorial driving other slugs from their home range in slug battles that are vicious, savage and slow. They rear up above their adversary and then drop onto the victim tearing at their flesh with their radula a collection of serrated teeth which can slash an unprepared victim open. But despite their territoriality local slug populations can be very high with all age and size groups represented.

One of their more endearing (and kinkier) traits is their method of reproduction they mate upside down in mid air hanging from a thread of slime. This always occurs on cool, rainy nights so it's seldom witnessed by humans but after their vertical assignation the two slugs - both now pregnant part ways and find some cool, damp, sheltered location to lay up to fifty small, clear spheres of jelly about the size of BB's. After a suitable interval the young sluglets hatch and then crawl out into the wide world to make their mark and continue their kind.

In spite of my admiration for slugs and slugdom in general I draw the line when they begin grazing on plants I consider "mine". So one spring, after numerous incidents and fruitless negotiations, I declared war on the slug clan and put out small trays of stale beer sunk into the ground up to their rims.

For the next two weeks I was busy emptying trays full of slug bodies each morning (they make great additions to compost heaps) and refilling them in the evenings with warm, stale, refreshing beer. While the area cleared was small (approximately a thousand square feet) the number of slugs dispatched was enormous - on the order of four thousand or so in total - and of all different sizes.

This is the best method of slug control I've found. Salt works but it stunts or kills the vegetation which is the whole point of getting rid of slugs. Poisoned baits work but bring a whole host of other problems. And repellents, while they usually work, don't get rid of the problem. In my opinion beer is best because if you have to kill something it should at least die happy.

Slugs still visit the garden occasionally, and I don't begrudge them their minuscule bit of salad but the days of wholesale grazing are gone.

If you entered this site on this page expecting to find a different subject, please consult our Natural Events Archive.

The information on this page is tailored to Southern Illinois, Southwest Indiana, Western Kentucky, and Southeast Missouri

Copyright © 2006 Jim Jung
Some images on this page copyright © 2006