Chemical Forms of Control

Metaldehyde (Meta)

Description:

Meta is a highly efficient form of slug control that provokes an extremely sensitive reaction only in slugs. It can be called a highly specific molluscicide. There are no reports of Meta causing harm to beneficial creatures such as earthworms or slug-eating ground beetles. <---!link to lonza---!>

Positive effects:

Meta is considered to be moderately toxic when ingested orally and does not produce any negative reactions on contact with the skin. Meta is neither teratogenic nor carcinogenic which means it will not cause malformations in a fetus or cause cancer. Slug pellets containing Metaldehyde can be freely purchased over the counter. The environmental toxicity is classed as low. In soil, Meta is rapidly broken down biologically into CO2 and water (on the leaf surface less than 7 days). Meta is stable in sunlight. Meta slug pellets remain effective for 2–3 weeks outdoors. Earthworms are not disturbed by Meta.

OR-CAL consumer pellets with Bitrex:

The OR-CAL consumer pellet contains a substance called Bitrex which is very unpleasing to the taste so that children or animals shouldn’t be harmed if they ingest the substance. Nevertheless, the same applies here as for all pest control products: slug pellets must always be used and stored out of the reach of children and pets. During use make sure that the pellets are scattered uniformly over the area you wish to disinfect.

Bitrex

Description:

Bitrex is the brand name of the bitterest substance yet discovered - Denatonium Benzoate. It is inert and odorless, but a few parts per million are enough to make products undesirable to eat in even the tiniest amounts.

Positive effects:

Evolution has given human beings a strong aversion to the bitterness that often marks out harmful plant or animal material. Studies have shown that children are particularly sensitive to these bitter tastes. That’s why denatonium benzoate is such a powerful deterrent to help prevent accidental poisonings in young children and household pets. <---!link to macfarlan---!>

Iron Phosphate

Description:

Iron phosphate is blended with EDTA (Iron Cheleate) and bait additives.

Positive effects:

The bait is biodegradable and can become part of the soil in your garden if the slugs do not ingest all of the pellets. After ingesting bait slugs and snails cease feeding in about three to six days.

Methiocarb

Description:

Used as a molluscicide, and can be formulated as a bait. This product has similar control to meta. However, this pesticide is restricted to licensed pest control operators only. It is classified as a carbonate.

Conventional Forms of Control

Slugs are very susceptible to drying out. In the early spring, cultivate your soil to expose their eggs to sunlight. This allows them to be exposed to drying air and predators. Keep excess moisture out of your garden. Use drip irrigation or soaker hoses rather than overhead sprinklers. If you use mulch in your garden, keep the mulch well back from the base of susceptible plants. Slugs are attracted to warm compost piles, so keep your pile separated from the rest of your garden.

Handpicking:

Handpicking is an extremely effective way of riding your garden of hundreds of slugs. Unfortunately it’s not the best way to rid your crop, in fact its most unpractical. However, if you aren’t squeamish about touching then you won’t need to use chopsticks, tongs, or hatpins to catch the offending pests. The best time to hunt for slugs is late evening or early morning; this is when they come out to feed. Drop them into a bucket of soapy water once you have caught them to quickly kill them. Do not use salt to kill slugs, besides being toxic to your plants, salt kills them slowly. This is a rather mean way to treat the animals, even though they don’t treat your garden with that much respect. The soapy water will kill slugs almost immediately so they don’t have to die a slow painful death.

Trapping and baiting:

Most gardeners choose either of these methods to prevent slug damage in their gardens. Attracting slugs into baits or to trap crops and then discarding them is a popular system. You may use wooden planks placed strategically, the slugs will be under the boards in the morning, and during the day, then handpick them and finish them off as described above.

Beer:

Slugs are attracted to the odors that are given off by the fermentation process. The most popular bait has been beer. However, not all beers are created equal. In 1987, a study at Colorado State University Entomology Professor Whitney found that Kingsbury Malt®, Michelob®, and Budweiser® attracted slugs far better than other brands. The beer will need to be replaced at least once a week or more as it looses its potency or becomes diluted by rain.

The range of slug traps is only a few feet so you need to supply a few throughout your garden. Never sink the containers with their rims flush with the soil level or you run the risk of drowning ground beetles, or other important slug predators. The rims should be 1" above the soil's surface. This can be very effective in the garden but again, it isn’t practical for a crop because of the cost as well as the upkeep.

Trap crops:

Certain plants seem to be favored by slugs and can be used to divert slugs from your prized plants. Particularly good trap crops include: green lettuce, cabbage, calendula, marigolds, comfrey, zinnias and beans.

Predators

hedgehogs, ducks, geese, frogs, nematodes and beetles.

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