Clouded Sulphur

Host plants

Clouded Sulphur caterpillars can only develop on their larval host plants. Plant one of these natives and you can host the full life cycle in your own yard (host plant associations per the Xerces Society (opens in new tab)).

• Trifolium pratense — see Tomcat Clover (same genus)
• Medicago sativa — see Little Bur-clover (same genus)
• Yellow Sweetclover (Melilotus officinalis)
• Golden Cassia (Chamaecrista fasciculata)
• Blue Wild Indigo (Baptisia australis var. minor)
• Yellow Wild Indigo (Baptisia sphaerocarpa)
• Bastard Indigo-bush (Amorpha fruticosa)
• Panicled False Indigo (Amorpha paniculata)
• Two Leaved Senna (Senna roemeriana)
• Lindheimer's Senna (Senna lindheimeriana)
• Trifolium repens

How to identify it

Look for a small yellow butterfly with rounded wings and subtle green or gray shading. Females can appear more white than yellow.

Good to know

• Females can vary from yellow to white in color
• Males are typically bright yellow
• They are important pollinators of clover and other meadow plants

Common questions

What do Clouded Sulphur caterpillars eat?

Clouded Sulphur caterpillars feed on Trifolium pratense, Medicago sativa, Melilotus officinalis, Chamaecrista fasciculata, Baptisia australis var. minor, Baptisia sphaerocarpa, Amorpha fruticosa, Amorpha paniculata, Senna roemeriana, Senna lindheimeriana, and Trifolium repens. These are the larval host plants the caterpillars must have to develop, per the Xerces Society and host plant records compiled from GBIF and iNaturalist.

Where do Clouded Sulphur live?

Clouded Sulphur is found across WY, ID, ME, NH and 36 more states.

When are Clouded Sulphur active?

Adult Clouded Sulphur are typically on the wing from May through September.