Emex australis

Southern three-cornered jack

Family: Polygonaceae · Type: annual · Not Native

Southern three-cornered jack is a naturalized annual found in the Central Coast bioregion in coastal sandy areas at elevations below 200 meters. Flowering from May to December, this plant produces small, inconspicuous flowers with distinctive triangular fruit. Growing with stems 1 to 5 decimeters tall, it spreads across sandy ground with a sprawling habit. Its leaves have petioles 1 to 6 centimeters long, with blades 1 to 5 centimeters long and 0.5 to 3 centimeters wide. The fruit is particularly notable for its three-cornered shape, with each face bearing 3 to 4 elongated depressions and sharp spines 3.5 to 6 millimeters long.

Habitat: Coastal, sandy areas

Bloom period: May-Dec

Elevation: < 200 m

Bioregions: CCo

Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Jepson eFlora, Cal-IPC, and more.