Based on 2,284 research-grade iNaturalist observations in Illinois, Spicebush Swallowtail is most often recorded in July; in Illinois it behaves like a summer visitor / breeder. It ranks #19 among butterflies recorded in the state in our data.
Papilio troilus
Spicebush Swallowtail in Illinois by month
Bars show research-grade observations per month. They mix true seasonality with how often people are outdoors, so treat small numbers with caution.
Also seen in Illinois in July
Monarch
Black Swallowtail
Red Admiral
Eastern Tiger Swallowtail
Silver-spotted Skipper
Pearl Crescent
Eastern Tailed-Blue
Common Buckeye
Places to look in Illinois
State ParkCahokia
Botanical GardenMorton Arboretum
National ForestShawnee National Forest
Botanical GardenChicago Botanic Garden
Botanical GardenLadd Arboretum
State ParkStarved Rock State Park
FAQ
When does Spicebush Swallowtail appear in Illinois?
Mainly July–August, with the most records in July.
How common is Spicebush Swallowtail in Illinois?
It ranks #19 by number of iNaturalist observations among butterflies in Illinois (2,284 records in our sample).