
Based on 1,871 research-grade iNaturalist observations in Maryland, Orange Sulphur is most often recorded in September; in Maryland it behaves like a summer visitor / breeder. It ranks #22 among butterflies recorded in the state in our data.
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Orange Sulphur in Maryland 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 Maryland in September
Huron Skipper

Monarch

Eastern Tiger Swallowtail

Common Buckeye

Pearl Crescent

Variegated Fritillary

Eastern Tailed-Blue

Black Swallowtail
Places to look in Maryland
Washington Monument State Park
Patapsco Valley State Park
Seneca Creek State Park
Calvert Cliffs State Park
Susquehanna State Park
Gambrill State Park
FAQ
When does Orange Sulphur appear in Maryland?
Mainly June–October, with the most records in September.
How common is Orange Sulphur in Maryland?
It ranks #22 by number of iNaturalist observations among butterflies in Maryland (1,871 records in our sample).