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- Water plantain Family: Alismataceae
Gregg arrowhead (Sagittaria longiloba)
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Gregg arrowhead is a native aquatic perennial that occurs in the Central Valley at low elevations (up to 100 feet (300 m). It resembles California arrowhead and is frequently found in wet excavated areas, irrigation ditches, and rice fields where stands are thin.
Seedling
Seedlings are submerged. Cotyledons (seed leaves) have narrow, light green leaves that taper to a point. Rectangular markings on the leaves help distinguish seedlings from ducksalad, river bulrush, and ricefield bulrush. The characteristic arrowhead leaf-shape appears with the third or fourth true leaf.
Mature plant
Leaves are much narrower than that of California arrowhead. The two bottom leaf lobes are about twice as long as the front lobe, whereas the two bottom leaf lobes of California arrowhead are shorter and broader.
Flowers
Flowers have three white petals. Unlike Gregg's arrowhead, California arrowhead has two (rarely three) flowers at the lowest flowering stem node.
Reproduction
Gregg arrowhead spreads through seeds and underground stems.
Related or similar plants
- Ducksalad, Heteranthera limosa
- River bulrush, Scirpus fluviatilis
- Ricefield bulrush, Scirpus mucronatus
- California arrowhead, Sagittaria montevidensis
More information
- Broadleaf ID illustration
- Calflora's distribution map
- For agriculture: UC IPM Pest Management Guidelines
