Swamp Beggarticks

Swamp Beggarticks

Bidens tripartita L.

Asteraceae (Sunflower Family)

▲ mature plant

▲ ▼ inflorescence going to fruit

Bidens tripartita L., Devil’s Beggarticks: (Bayer Code: BIDTR; US Code BITR)

Native summer annual that grows 1-3 feet tall and has a green, hairless stem
Has opposite simple lanceolate leaves with toothed margins, although some leaves may be deeply three-lobed
Flower heads usually lack ray flowers and has 20-40 yellow disk flowers
Seed is elongated triangular with 2 barbs attached to tip that let it attach to passing animals
Commonly found in wet soils, along ponds, rivers, streams, lakes
Some similar species:
- Spanish Needles (Bidens bipinnata) has finely-divided (bipinnately compound) leaves, 1-5 very short (0.25 inch) ray flowers (petals) per head and long, slender, needle-like seeds with burs at their tip
- Nodding Beggarticks (Bidens cernua) has simple lanceolate leaves with toothed, lanceolate leaflets, 6-8 ray showy flowers (petals) per head and burs and seeds similar to devil’s beggarticks
- Tickseed Beggarticks (Bidens aristosa) has pinnately compound leaves with toothed, lanceolate leaflets ( leaflets often more narrow than devils beggarticks) and 6-8 showy ray flowers (petals) per head and triangular, 2-burred seeds
- Devil’s Beggarticks (Bidens frondosa) has pinnately-compound leaves with toothed, lanceolate leaflets, flowers lack ray flowers and the burs are short and attached to a triangular seed

(Posted January 19, 2019)