Vulnerabilities and Preferences

Some behaviors of slugs

  • Alarm mode: contract to a smaller size, when disturbed or when cold/dry; secrete differently colored mucus
  • Detect the presence of ground beetles by olfactory cues: Become less active, produce excessive mucus, & tail-wagging occurs 
  • Neonates don’t move as far as adults in the field; eat differently than adults: primarily fungi- & algae-eaters, but can eat plant parts
  • Weather can influence: Poison uptake and slug recovery
  • Omnivores: feed on dead slugs, pet food, earthworms, live and decaying vegetation,and algae, fungi, lichens
  • Home-bodies: Travel only short distances, unless unfavorable conditions
  • Aestivate: restrict their activity (months) when conditions unfavorable
  • Nocturnal: mainly night feeders, but will also feed during the day when environmental conditions are suitable
  • When irritated: Can thrive in moist crevices, air gaps between clods of soil, in vole holes, earthworm burrows
  • Travel per day: 
    • Arion lusitanicus = 9.8 ft (3 m)
    • Arion hortenensis = 3 ft (1 m)
    • Deroceras reticulatum  = 9.8 ft (3 m); Can travel up to 40 feet (12.2 m) in one night. 

Limax maximus found on the OSU campus

What they like

  • 100% humidity
  • Negligible wind <5mph
  • Cracks and crevices
  • Surface debris (e.g., straw)
  • Temp 40 - 70°F (60°F)
  • Light rain and fog
  • Dark & shady; overcast
  • Acidic soils & clay
  • Cotyledons and seedlings
  • Banana splits

What they don't like

  • Dry conditions
  • Winds > 5-10 mph
  • No hiding places
  • Lack of surface debris/straw
  • Temp < 34°F, > 85°F
  • Driving rain
  • Sunlight
  • Lime | sand
  • Less so established plants
  • Salt


Rainfall plays a big role

Rainfall is a critical environmental factor forcing slugs upward where they feed on the surface in Oct and Nov, while favorable weather conditions last. Treat when a window of opportunity exists in the fall.

Water Table Effects