The egg hatching rate is higher during warm, dry seasons, sometimes leading to outbreaks of large swarms.

This female katydid has a long ovipositor for depositing eggs in vegetation.

She has picked up a spermatophore (the white ball beneath her ovipositor: a nuptial gift from a male).

Katydids in northern Illinois include:
Black-legged Meadow Katydid
Greater Angle-wing Katydid.