Deep Yard Holes: Cicada Emergence or Cicada Killer Wasps?

Quarter-Sized, 12-Inch Deep Holes with No Soil Mounds

Early-season holes (tiny to quarter-sized, 12″+ deep, no excavated soil) in a backyard with hydrangeas previously visited by small flies suggest emerging cicada nymphs.

Cicada Nymph Emergence

• Nymphs live underground 2–17 years, feeding on root xylem.
• Emergence holes are deep, narrow, clean—no soil piles.
• Adults fly to trees; holes naturally fill in.
• No treatment needed; event is temporary.

Later in Season: Cicada Killer Wasps

• Females dig burrows (6–8″ horseshoe mounds) to provision with paralyzed cicadas.
• Males are territorial (dive-bomb) but stingless.
• Females can sting but rarely do.
• Control only if high-traffic areas: dust burrow entrances with carbaryl (Sevin) or bendiocarb.

Key Distinction

Early season + no mounds = cicada emergence. Late summer + mounds = cicada killers. Both are benign components of the ecosystem.