CHOMPING DOWN GARDEN PLANTS, CAUSING INJURY AND DEATH
Garden Slug, Deroceras reticulatum, European Slug, Arion
Hangout: Under rocks, flower pots, other damp locations;
also in tall grass, weeds
Physical Features: Soft bodied; similar to
snails with no shell; 1/4" to 10" long; eyestalks that look
On cool, rainy days and nights, slugs point their gruesome looking eyestalks
in the direction of your garden. Their subtle, slow movements belie the
unsightly destruction they can cause to plant leaves. Making slug populations
even harder to control, they can reproduce at any time of year. Each slug
has both male and female reproductive parts, so they cross-fertilize to
reproduce. Three to 40 eggs are laid at a time. Up to 400 eggs can be
laid by one slug each year! As long as the weather is cool and moist,
eggs will hatch in just a few weeks, putting even more criminals on the
prowl. After only three months, offspring can reproduce.
WATCH OUT FOR SLIME TRAILS. SLUGS LEAVE BEHIND A TRAIL OF CLEAR MUCUS
THAT TURNS SILVERY WHEN DRY.
Go Get'em, Slugger!
1. Patrol the area
- Patrol during wet weather.
- Search slug hideouts, like
shady spots and under rocks and pots.
- Look for slug eggs (milky-looking,
round, squishy eggs) in the soil of your garden bed. This will give
you an idea of springtime populations.
- Be on the lookout for silvery
- Record what you see. Estimate
slug populations in a given area when you patrol to make comparisons
of population growth easier.
2. Make a positive I.D.
- There are many other species
of slugs in this area, but the usual culprits in backyard crimes are
the garden and European slugs.
3. Do a thorough background
- Slugs are attracted to a
chemical given off by ripe fruits called ethylene. This same chemical
is found in beer, which is why beer traps are so effective.
- Slugs are also attracted
to tender plants and seedlings.
4. Determine the danger
- Look at damaged plant leaves
and estimate the percentage of the leaf that is missing due to slug
- Plants can bounce back from
damage as long as it's not too much. How much is too much? Established,
healthy plants can make a comeback from heavy assaults, while seedlings
may be at risk after just a few bites.
- Keeping track of the size
of slug invasions will help you decide if the problem is getting better
5. Make a plan
- Do-Nothing Method
-Pay close attention to how much feeding damage your plant can tolerate.
-In the summer you can count on drier, warmer weather to keep slugs
in hiding, rather than hurting your plants.
-Damage in the Fall is less of a concern
- Manipulative Measures
-Get rid of hideouts, like old pots, debris piles, and long grass, where
slugs seek shelter when the weather turns sunny and warm.
-Break out the S.W.A.T. team! Squish slug eggs. Use a shovel to cut
slugs in half or maybe you can even squash them barehanded. Or stomp
-Drown the dastardly drunks in beer traps. Slugs will blissfully dive
into partially filled cans of beer pushed into the soil, plunging to
their deaths. Or cut a hole two inches above the bottom of a paper cup.
Fill with one inch of beer and place near plants.
-Are they always attacking the same type of plant? Get rid of it and
you might get rid of your slug problem. Sometimes changing cultivars
eliminates the problem. Slugs love most hostas, but they won't eat the
-Defend your plants with copper armor! Line gardens, containers or any
outside plant with copper strips purchased in rolls from garden stores.
The interaction of copper with the slime on their bodies gives slugs
- Secret Agents
-Beef up security by making your landscape appealing to slug-eating
birds, frogs, and snakes (the Lake Whatcom area does not have poisonous
ones). Set up birdhouses, birdbaths or maybe even a little pond with
-Slug-eating ground beetles are mortal enemies to these intruders. Reduce
your use of pesticides to keep them stalking slugs.
- Armed and Dangerous
-Non-chemical methods work well against slugs, but if you are determined
to use something like commercial slug bait, use as little as possible.
Follow directions on the label for use, storage, and disposal.
-Put the bait in some kind of container, not directly on the ground,
to prevent toxins from eventually seeping into Lake Whatcom.
-Baits with ferrous phosphate as the active ingredient are less toxic
than others that often contain metaldehyde, a nerve poison which is
dangerous for cats and dogs.
6. Evaluate the results
- Since slugs have plant preferences,
record which plants were slugged and the extent of damage. Also keep
a record of strategies you used and if they sent slugs on the run.
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