Plants of the San Marcos Foothills Preserve

Conium maculatum (poison hemlock)

Common, non-native annual herb found throughout the Preserve in scattered locations but also in large stands, particularly along Atascadero and Cieneguitas Creeks. Flower are white. Blooms in spring. This plant is highly toxic if ingested.

Conium maculatum (poison hemlock) seedlings mixed with Brassica nigra seedlings. NON-NATIVE Pictured in winter.

Conium maculatum (poison hemlock) seedlings. NON-NATIVE Pictured in winter.

Conium maculatum (poison hemlock). NON-NATIVE Pictured in summer.

Conium maculatum (poison hemlock) seedlings. NON-NATIVE Pictured in winter.

Conium maculatum (poison hemlock) seedlings. NON-NATIVE Pictured in winter.

Conium maculatum (poison hemlock) maturing seedlings. NON-NATIVE Pictured in winter.

Conium maculatum (poison hemlock). NON-NATIVE Pictured in summer.

Conium maculatum (poison hemlock) seedlings. NON-NATIVE Pictured in winter.