Common ragwort

Senecio jacobaea

Introduction: Senecio jacobaea, commonly known as common ragwort, is a biennial or short-lived perennial flowering plant belonging to the Asteraceae family. Native to Europe, it has become naturalized in various parts of the world. While common ragwort has ecological roles, it is also considered toxic to livestock, and its uncontrolled spread can impact pastures and rangelands.

Identification:

1. Morphology:

  • Height: Common ragwort typically grows to a height of 30 to 100 centimeters.
  • Leaves: The leaves are deeply lobed and form a basal rosette in the first year, with smaller, alternate leaves on the stems in the second year.
  • Stems: Erect, branched stems covered in fine hairs.

2. Flowers:

  • Inflorescence: Bright yellow, daisy-like flowers are arranged in flat-topped clusters.
  • Blooming Period: Common ragwort blooms from late spring to early autumn.

3. Habitat:

  • Commonly found in grasslands, meadows, pastures, roadsides, and disturbed areas.
  • Thrives in well-drained soils and is often seen in open, sunny locations.

Ecological Roles:

1. Biodiversity Support:

  • The flowers of common ragwort attract pollinators, including bees and butterflies, contributing to local biodiversity.

2. Soil Stabilization:

  • The plant's extensive root system helps stabilize soils, particularly in disturbed or eroded areas.

3. Nitrogen Accumulation:

  • Like many plants in the Asteraceae family, common ragwort can accumulate nitrogen in its tissues.

Toxicity:

1. Pyrrolizidine Alkaloids:

  • Common ragwort contains pyrrolizidine alkaloids, which are toxic to livestock and can cause liver damage.
  • Ingestion of the plant, especially in hay, can lead to cumulative toxicity.

2. Livestock Health Impact:

  • The toxicity of common ragwort poses a threat to livestock such as horses, cattle, and sheep.
  • Control measures are often implemented to prevent livestock access to areas where the plant grows.

Control and Management:

1. Manual Removal:

  • Hand-pulling or cutting common ragwort before seed production is a common method for small infestations.
  • Care must be taken to wear protective clothing due to potential skin irritation.

2. Herbicide Use:

  • Selective herbicides targeting broadleaf weeds can be used for control, especially in larger infestations.
  • Herbicides need to be applied according to recommended guidelines.

3. Livestock Management:

  • Livestock should be prevented from grazing in areas where common ragwort is prevalent.
  • Regular monitoring of pastures is important to identify and address any new infestations.