Yellow Water Lily

Also known as:
Yellow Pond-Lily, Spatterdock, Cow Lily, Brandy Bottle
Northern temperate regions

General description

Perennial herb. Large leathery floating green leaves <40cm x 30cm, lettuce-like submerged leaves. Forms large, spongy rhizomes. Bright yellow flowers smelling strongly of alcohol above surface. Green flask shaped fruit split open to release seeds.

Still or slow flowing fresh water <2m deep: lakes, streams.

Seeds, rhizome fragments spread by water.

Mats block waterways, impeding drainage, disrupting recreational activities, choking hydro turbines. Out-competes native species.

Site management

Regular follow up required.

Recommended approaches

1. Hand clear small infestations.
2. Weedmat at least 3-4 months.
3. Spray emergent foliage, repeat as necessary (100ml glyphosate/10L, use glyphosate formulation approved for use over water).

Caution: when using any herbicide or pesticide PLEASE READ THE LABEL THOROUGHLY to ensure that all instructions and safety requirements are followed.

Similar species

water poppy
Hydrocleys nymphoides

Water poppy has much smaller floating leaves, has a distinctive enlarged mid vein, and lacks large rhizome.

Nymphoides geminata

Marshwort has much smaller floating leaves, has fringed petals and lacks the large rhizome.

fringed water lily
Nymphoides peltata

Fringed water lily has much smaller floating leaves, has fringed petals and lacks the large rhizome.

Mexican water lily
Nymphaea mexicana

Mexican lily has a much rounder leaf and lacks the thick spongy rhizome.

Search tags

RPMS status

Surveillance - Whole Region
National Pest Plant Accord species - nationwide
yellow water lily - Main species image