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ARS Home » Pacific West Area » Hilo, Hawaii » Daniel K. Inouye U.S. Pacific Basin Agricultural Research Center » Tropical Crop and Commodity Protection Research » Research » Publications at this Location » Publication #199619

Title: Controlling slugs and snails in orchids

Author
item Hollingsworth, Robert

Submitted to: Orchid World
Publication Type: Trade Journal
Publication Acceptance Date: 1/12/2007
Publication Date: N/A
Citation: N/A

Interpretive Summary: Slugs and snails are pests of orchids, preferring tender plant tissues such as flowers and root tips. Unlike many insect pests which feed only on certain types of plants, most species of slugs and snails are generalists, feeding on green plants, algae, fungi, decaying plant matter, or decaying animal matter. This feeding habit, in combination with their relatively large size, makes it difficult to control slugs and snails using contact poisons applied to plants. Many control options are available if the pest does not reside full-time on greenhouse benches. For example, copper in various forms can be used as a repellent on greenhouse bench supports. However, for smaller species of slugs and snails which live within the planting medium, chemical control may be the only viable option. Experimental control methods include various natural chemicals such as neem, diatomaceous earth and caffeine. However, most growers will want to choose a product specifically registered and labeled for slug and snail. The most popular types of products, which are also among the most effective, are those containing metaldehyde. Metaldehyde products come in various forms, including liquid, granular and bait formulations. There are advantages and disadvantages to each type. Great care should be taken to avoid accidental poisoning of pets and other domesticated animals. Metaldehyde products, particularly baits, are both attractive and deadly to pets such as dogs. A new type of product which is more user-friendly and available to all is a food bait pellet containing 1% iron phosphate. Unlike metaldehyde baits, baits containing iron phosphate are considered safe to use around animals, including dogs. Iron phosphate baits can be just as effective as metaldehyde baits, but relative efficacy will depend on the species involved.

Technical Abstract: Slugs and snails are pests of orchids, preferring tender plant tissues such as flowers and root tips. Unlike many insect pests which feed only on certain types of plants, most species of slugs and snails are generalists, feeding on green plants, algae, fungi, decaying plant matter, or decaying animal matter. This feeding habit, in combination with their relatively large size, makes it difficult to control slugs and snails using contact poisons applied to plants. Many control options are available if the pest does not reside full-time on greenhouse benches. For example, copper in various forms can be used as a repellent on greenhouse bench supports. However, for smaller species of slugs and snails which live within the planting medium, chemical control may be the only viable option. Experimental control methods include various natural chemicals such as neem, diatomaceous earth and caffeine. However, most growers will want to choose a product specifically registered and labeled for slug and snail. The most popular types of products, which are also among the most effective, are those containing metaldehyde. Metaldehyde products come in various forms, including liquid, granular and bait formulations. There are advantages and disadvantages to each type. Great care should be taken to avoid accidental poisoning of pets and other domesticated animals. Metaldehyde products, particularly baits, are both attractive and deadly to pets such as dogs. A new type of product which is more user-friendly and available to all is a food bait pellet containing 1% iron phosphate. Unlike metaldehyde baits, baits containing iron phosphate are considered safe to use around animals, including dogs. Iron phosphate baits can be just as effective as metaldehyde baits, but relative efficacy will depend on the species involved.