How to get rid of orchid snails?

[JanS]

Greetings!
I've been in a battle with "orchid snails" (also called bush snails) for quite some time and have done quite a bit of research on them. I've followed various web discussions and suggestions and thought members of this forum would appreciate a summary...as well as for me to pose the on-going question - How to best get rid of the bastards?

Orchid snails are the very small snails that hide in the potting medium during the day, crawl out at night and eat the new root tips of many orchid species. Other bigger snails and slugs seem to be much more easily controlled with readily available baits, but these little guys do not seem to be attracted to them. Here's an excellent summary scientific article showing photos and discussing the best tested treatments:

http://www.ctahr.hawaii.edu/oc/freepubs/pdf/MP-1.pdf

I was ready to buy the 25% metaldehyde "Slug-fest" liquid and get rid of my problem once and for all - only to find out it is unavailable - the EPA banned it a few months ago. Note that the research in the above article states that metaldehyde-containing baits are NOT effective! Lilly-Miller still sells a spray (made for them by the Slug-fest company) but at much lower concentrations. I guess I'll give it a try (it appears soaking the metaldehyde into the bark to create actual contact with the snails is the only way to go).

One other note: Some years ago there was research claiming that caffeine in 3-5% concentration will kill the snails - apparently by giving them a heart attack. I've seen a lot of discussion about how to use this method, or using coffee grounds, etc. Short of purchasing pure powdered caffeine from a chemical supply, the only way to even get close to a 3-5% solution is to buy caffeine tablets at a drug store, grind them up and dissolve them in the appropriate amount of water. I did just that but there are complications: First, the tablets consist of mostly chalky filler, so for 50 tablets' worth you end up with less than a liter of liquid (to get close to 4%) and a huge amount of chalky mud, which I settled out and just recovered the liquid which I ran through a number of infested orchid pots. At $10 or so for a 50 pill bottle, this procedure is not very economical for even a moderate number of plants. Results? I must say it did seem to help for a while but (at least with a single treatment) the snails were back in a month or so - either not all died and/or the caffeine does nothing to the eggs. Hope this info helps for anyone contemplaiting the "Heart Attack Remedy".

So with this said - does anyone have experience with a truly effective treatment for these extremely destructive pests? What do large orchid growers do?

Thanks!

[Baz in Oz]

The best cure is prevention. My SH #2 is almost snail proof and the problem has almost vanished.

Previously, with SH #1 I found pyrethrum was effective as it allegedly kills anything that sucks or chews. Make sure you use enough spray to wet the potting medium thoroughly. Early morning and late night hunting expeditions caught a lot of snails and made me feel better and gave the snails a little excitement but didn't solve the problem.

One grower I heard of solved the problem by getting his grandkids a pet turtle which he kept in his SH.

Good luck!

Baz

[thakshila smith]

How to keep a turtle? isn't it a vegetarian?
Any way see this . My friends.

[Baz in Oz]

When I say 'turtle' I am including tortoises (I can't tell the difference anyway) and some on ours down here are definitely carniverous as I have caught them on fishing lines in fresh water while trying to catch fish and aren't they fun trying to unhook them!

I read about the turtle one on an orchid club web site so it is only hearsay or maybe it should be readsay.

I still lean towards the pyrethrum as it is relatively benigh and agriculturally, it has a withholding period of 24 hours and it is a natural product derived from chrysanthemums.

Baz

[JanS]

Well, I now have 4 turtles roaming around the greenhouse but they seem to be more interested in eating the orchids than the snails....

Seriously, I totally agree that prevention is the best cure. In my case, I had no bush snail problems for years, then must have introduced them with some plant I bought somewhere. I must have compounded my problem by using a large container to water a number of my orchids at a time by dipping them together in water in the container. I guess that's how the eggs spread from one batch to another.

I have also tried to get rid of the pests by leaving infected pots completely submerged in water for an hour or so - the snails crawl out above the water line and I can pick them off...but similar to Raz's nightime hunts, you get some to make you feel good but ultimately the problem remains. I'll try the pyrethrum idea. At this point, I'm ready to try WMDs. It's agonizing to see one of my favorite old orchids slowly die an agonizing death because each of the last 2 years when the new pseudobulb tries to grow new roots they get eaten off and the poor plant is just living off its old reserves...UGGGH!

[littlefrog]

I use iron phosphate slug bait (Sluggit, a few other brands). Seems to work for me, and it is non-toxic to you and your pets. Unless you eat a few pounds of it, anyway. Pretty cheap, too.

You can trap molluscs with lettuce leaves. Get some iceberg or romaine, put it where you have the problem, and first thing in the morning (or in the middle of the night), check the leaves. Squish critters, repeat. Trapping (and bait) only works on adult molluscs. You need to repeat the process for several weeks (or months!) to make sure you get the eggs as they hatch.

Another trap that works well is stale beer in a tuna fish can or similar container. Don't use good beer, the snails don't appreciate it and you might.

Rob

[Ray]

Anecdotal evidence only, but years ago I used to keep the dregs from the coffee pot in an old milk jug, adding about 10% isopropyl alcohol to quash any fungal slime or bacterial growth, and just poured it directly on the affected plants.

The snails seemed to have gone away, and I have not seen one since.

[Iray]

Ray, was the treatment effective? I got little snails in my miltoniopsis media and I'm not sure what to do about it :s
Would a soak in diluted hydrogen peroxide with water work? Or would it damage the roots? I repotted it less than a month ago, so I would like to avoid it
Thank you in advance!

[RJSquirrel]

I use 'Sluggo'/Iron Phosphate if I see any, otherwise I just dust the plants up with Diatomaceous earth "Insect Dust" for prevention. Insect dust cuts up soft-bodied pests, then they dry up bec they are leaking. It can be sprinkled around garden beds or individual plants, and mixed with water to make a spray.

Diatomaceous earth is less effective when wet, so use during dry weather. Wear protective gear when applying, as it can irritate eyes and lungs. Be sure to buy natural or agricultural grade diatomaceous earth, not pool grade which has smoother edges and is far less effective.

Dont have snails or slugs eaten my buds n roots. Cold burglar steals em but they arent food.


PS 'Sluggo' will get moldy and grow hairy filaments that can be distressing but no worries as it washes off and doesnt harm the plants.


those Big Apple snails go good with butter and garlic roasted on the pit till they boil out

[Bud]

I also used dregs from coffee; sprinkled them around the mix and I had slices of potato placed around the mix and in the morning I find the small snails attached to the potato.
I just ended up repotting the whole plant in case there were eggs in the mix.
Slugs and snails eat leaves and bulbs. It may not kill the plant but it leaves ugly scars and holes on leaves.