Appearance

Senecio madagascariensis is an annual or biennial herb that can grow up to 23.6 in. (60 cm) tall.

Foliage

Leaves are alternate, up to 4.7 in. (12 cm) long, and bright green. Cauline leaves are linear to lanceolate with an acute apex, denticulate margins, and can be petiolate, subsessile, or sessile.

Flowers

The small flower heads are 0.5-1 in. (12-25 mm) in diameter. Involucral bracts are acute, glabrous, and 0.16-0.24 (4-6 mm) long. Outer bracts are lanceolate, acute, purple tinged, and 0.04-0.08 (1-2 mm) long. Ray florets are yellow and 0.3-0.6 in. (8-14 mm) long. Disk florets are perfect and yellow as well.

Fruit

Fruits are 0.06-0.09 in. (1.4-2.2 mm) long, 9 to 10 ribbed, and pubescent between ribs. Seeds are white and 2 to 3 times as long as the fruit.

Ecological Threat

Senecio madagascariensis can be found in a wide variety of habitats but prefers fertile, well-drained, disturbed soils. It is considered native to southern Africa and Madagascar.

Selected Images

---

Maps

---

Invasive Listing Sources

---

• Federal Noxious Weeds
• Hawaii Noxious Weeds

References

---

Common Name Reference: USDA, NRCS. 2010. The PLANTS Database. National Plant Data Center, Baton Rouge, LA, USA.

Scientific Name Reference: USDA, NRCS. 2010. The PLANTS Database. National Plant Data Center, Baton Rouge, LA, USA.