Fireweed

Fireweed (Senecio madagascarensis) is a highly invasive daisy-like herb from Madagascar. It was first discovered on the island of Hawai‘i in the 1980s. It later spread to Kaua‘i, O‘ahu, and Lana‘i through contaminated grass seed imported from Australia—where fireweed is also invasive.

Each plant can produce 30,000 seeds per year. Seeds are easily spread by wind, water, and carried by people, animals and vehicles. It invades pastures, roadsides, and disturbed ground. It is toxic to livestock when eaten, causing sickness and even death.

Fireweed has been successfully eradicated from Hawai‘i. However, it is invasive in many places around the world, and can reappear at any time. Controlling invasive plants is a practice that requires constant vigilance. The first step is to plant native species before importing any introduced plants. Invasive species often arrive as hitchhikers with imported plants and products.