Image: Senecio madagascariensis plant13 (16143326805)

Description: Introduced, yearlong-green, annual or biennial, erect herb to 70 cm tall. Leaves are variable, mostly 2-8 cm long and lanceolate or elliptical, but never deeply dissected. Fllowerheads are loose clusters of yellow heads, each to 2 cm diameter. There are usually 13 (12-15) outer (petal-like) ray flowers and one row of 20-21 bracts. Flowering is year-round, but mostly from autumn to spring. A native of southern Africa, it is a common weed of pastures and disturbed sites. Most prolific on lighter-textured, acid, well-drained, low to medium fertility soils. Seeds are spread long distances by wind. More abundant where pastures are overgrazed or disturbed. Contains toxins that cause irreversible liver damage. Poisoning is usually chronic, leading to ill-thrift and eventually death if stock continue to graze it. Horses and cattle (especially young stock) are most susceptible, sheep less so, and goats the least. Not very palatable for cattle or horses, but goats and sheep will seek it out. More likely to be eaten if stock graze after slashing, as they cannot discriminate between fireweed and pasture. Best controlled using a number of methods, including strong pastures, grazing and herbicides. A dense, well-managed pasture can limit fireweed establishment, plant size and seed production. Hand pulling and bagging is very effective for controlling small/light infestations. Herbicides are most effective if used on smaller plants, preferably before flowering.
Title: Senecio madagascariensis plant13 (16143326805)
Credit: Senecio madagascariensis plant13
Author: Harry Rose from South West Rocks, Australia
Usage Terms: Creative Commons Attribution 2.0
License: CC BY 2.0
License Link: https://creativecommons.org/licenses/by/2.0
Attribution Required?: Yes