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Nuphar variegata


Spatterdock colony
Spatterdock in-situ

Habitat: Spatterdock is part of the floating-leaved plant community, growing in depths up to 2 meters. It is especially abundant in still or slow moving waters with soft sediments. Spatterdock can grow in sun or shade, but flowers more readily in good light.

Description: Spatterdock is a floating-leaved perennial. The leaves are elongate and heart-shaped, 7 to 40 cm long, with rounded lobes. The lobes are parallel or overlapping and the leaf notch is usually less than half the length of the midrib. The leaf and flower stalks emerge from a thick spongy rhizome marked with a spiraling pattern of leaf scars. The leaf stalks are thick and elastic. One side of the stalk is rounded, flaring out at the edges to create wing-like structures that run the length of the stalk. The other side is more flattened. The stalks are unbranching; each stalk supports one leaf. The flowers of spatterdock are yellow and ball-shaped with 5 or 6 petals around a yellowish-green stigmatic disk. The disk eventually develops into a large seedpod that is shaped like a barrel or vase.

Spatterdock Flower
The flowers are yellow and ball-shaped:
the stigmatic disk develops into a
vase-shaped seedpod

U.S. Range: Spatterdock is one of the most common aquatic plants in New England and is widely distributed in Maine. Its range includes much of the northern United States.

Annual Cycle: Spatterdock overwinters as rhizomes and seeds. New leaves begin to emerge from the rhizomes early in the summer. Later, flowers are borne above the floating leaves, often blooming all summer long.

Spatterdock stem
The leaf stalks are thick and elastic

Value to the Aquatic Community: Spatterdock is an important food source for a wide variety of wildlife including, waterfowl, deer, muskrat, beaver, and porcupine. The leaves offer shade and habitat for fish and invertebrates.

Look Alikes: May be confused with European frogbit, yellow floating heart, small and large yellow pond lilies (both species uncommon in Maine and not included in this guide), little floating heart, watershield, and fragrant water lily.

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Spatterdock flower Spatterdock seed Spatterdock in-situ Spatterdock stalk Spatterdock cross-section Spatterdock range map Spatterdock illustration

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