Zygophyllaceae

Big caltrop

Kallstroemia maxima (L.) Hook. & Arn.

Family: Zygophyllaceae
Genus: Kallstroemia

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Big caltrop (Kallstroemia maxima) — FlowerPhoto: 曾昱承 Yu-Cheng Zeng, CC BY 4.0, from iNaturalist

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Common names

By language (1)

English: Big caltrop

Synonyms

Kallstroemia canescens Rydb.
Kallstroemia tribulus Meisn.
Tribulus decolor Macfad.
Tribulus dimidiatus Raf.
Tribulus maximus L.
Tribulus trijugatus Nutt.
Tribulus tuberculatus Sessé & Moc.

Flowers

In flower: January to November (from 163 flowering iNaturalist observations worldwide)

Characteristics

Growth habit: Forb/herb
Lifespan: Annual
In the US and Canada: Lower 48 states: native, Puerto Rico: native, U.S. Virgin Islands: native

Photos

FlowerPhoto: 曾昱承 Yu-Cheng Zeng, CC BY 4.0, from iNaturalist
FlowerPhoto: Sam Droege, CC0, from iNaturalist
FlowerPhoto: Ricardo Betancourt Sánchez, CC BY 4.0, from iNaturalist
FlowerPhoto: laiet17, CC0, from iNaturalist
FlowerPhoto: chiuluan, CC BY 4.0, from iNaturalist
Photo: Jochen Essig, CC BY 4.0, from iNaturalist
Photo: ritirene, CC BY 4.0, from iNaturalist
Photo: Oscar C. González Martínez, CC BY-SA 4.0, from iNaturalist
Photo: Steven Bodzin, CC BY 4.0, from iNaturalist
Photo: Tereso Hernández Morales, CC BY 4.0, from iNaturalist
Photo: Terry Woodward, CC BY 4.0, from iNaturalist
Photo: David Garza, CC BY 4.0, from iNaturalist

More in Kallstroemia

Sources: classification, synonyms from World Flora Online Plant List (2026-06, CC0 1.0); common names, popularity from Wikidata (2026-10-26, CC0 1.0); common names, US characteristics from USDA PLANTS Database (2025-05-29, CC0 1.0). About our plant data.