Bugs, slugs and snails in the garden

Wow! Look what the rain brought. Slugs and snails are really enjoying those dark damp places where they can feed all night without being disturbed. My sweet potato vine, shown above, is thriving in a shady spot in the garden, but the snails are munching on it as fast as it is putting out new growth.

So, what to do? There are some safe methods to control snails, but they require vigilance. First, depending on your need to rest at night, you can take a bucket and flashlight and begin collecting them from under leaves around dark.

Secondly, you can use beer traps. These are effective within the immediate area surrounding your trap, so you may need several. Simply sink a shallow bowl (old margarine tubs work) into the ground and pour an inch or so of beer into the bottom. The yeast in the beer attracts the snails and slugs and they drown in the beer. Mike Merchant, Extension Urban Entomologist in Dallas, says folks tell him Budweiser and Michelob brands work best. If you don’t want to use beer, sugar water with a bit of yeast added also works.

Since snails and slugs are long-lived, you can trap them by placing fruit rinds on the ground for them to hide under and then pick them up and destroy them. Remember they eat all night, so search for them early, before the sun rises. Slugs can be sprayed directly with household ammonia. A 5 percent solution (1 part ammonia to 19 parts of water) works well on slugs, but this is not going to penetrate a snail’s shell, and too much sprayed on a plant will destroy foliage.

You can also use baits with the chemical metadehyde. They work, but are a danger to pets, wildlife, etc. and you have to turn off the sprinkler for 3 to 4 days after setting them out. If you choose this method, please follow the directions carefully and keep the dog out of the area.

Now to the really serious problem — mosquitoes. We can’t help the rain, but we can keep from breeding mosquitoes in the saucers under flower pots, wheelbarrows, bird baths, wading pools, and bird feeders. Empty these after a rain. The main culprit for transmission of West Nile virus is the Southern house mosquito, Culex quinquefasciatus, and we’ll see more of them as things dry out.

Use repellents every time you step out to work in the garden or enjoy the backyard. DEET works and provides 5 to 6 hours of protection. If you don’t like the smell or feel of DEET, there are some new alternatives. A natural product, oil of lemon eucalyptus provides protection and you can find it under the name Repel Lemon Eucalyptus. OFF botanicals also is using eucalyptus as a main ingredient. Another plant-based repellent, Bite Blocker, provides protection, but for only about one and a half hours. Picaridin is a synthetic repellent in use in Europe since 1997 and recently introduced here as Cutter Advanced.

For more information on insects, check out Merchant’s Web page at http://citybugs.tamu.edu. For information on West Nile virus in Texas, go to www.dshs.state.tx.us/idcu/dis ease/arboviral/WestNile/.

Barbara Storz serves South Texas residents as the area Extension Horticulturist. You can reach her at (956) 383-1026 or by e-mail at bstorz@tamu.edu.