Packera

Golden Ragwort Senecio aureus Flower 2184px

Packera hesperia 4676

Packera sanguisorbae (Asteraceae)

Packera is a genus of flowering plants in the Asteraceae family, which is one of the largest families of plants, known for its members having composite flower heads. The genus was named after the Canadian botanist John G. Packer. Packera species are commonly found in a variety of habitats across North America, including meadows, woodlands, and alpine regions. They are known for their vibrant flowers, which can be yellow, pink, or purple, depending on the species. The genus includes both annual and perennial plants, making it diverse in its growth habits and life cycles.

Description

Plants in the genus Packera are characterized by their composite flower heads, which consist of both ray and disc florets. The leaves of these plants can be basal, cauline, or a combination of both, and their shapes can vary widely from lanceolate to ovate. The fruit of Packera plants is typically a cypsela, which is a type of dry, indehiscent fruit commonly found in the Asteraceae family.

Taxonomy

The genus Packera was previously included in the larger genus Senecio, but phylogenetic studies based on DNA sequences have led to its recognition as a separate genus. This reclassification is part of a broader effort to refine the taxonomy of the Asteraceae family based on genetic data. The genus is divided into several species, each adapted to specific environmental conditions and having distinct morphological characteristics.

Ecology

Packera species play a significant role in their ecosystems. They are important sources of nectar for a variety of pollinators, including bees, butterflies, and other insects. Some species are adapted to harsh conditions, such as alpine environments, where they contribute to soil stabilization and the overall biodiversity of the area. The adaptability of Packera species to different habitats makes them interesting subjects for studies on plant ecology and evolution.

Conservation

While many Packera species are common and not considered at risk, some are rare and face threats from habitat loss, invasive species, and climate change. Conservation efforts for these species include habitat protection, restoration projects, and research on their ecology and genetics to inform conservation strategies.

Selected Species

• Packera aurea (Golden Ragwort)
• Packera obovata (Roundleaf Ragwort)
• Packera plattensis (Prairie Ragwort)
• Packera paupercula (Balsam Ragwort)

See Also

• Asteraceae
• Senecio
• Flowering plant
• Pollinator