Family: Geraniaceae

Origin, Description & Uses
Erodium cicutarium, commonly known as alfilaria or redstem filaree, is native to the Mediterranean region but is now widely distributed across many parts of the world, including Hawaiʻi. This low-growing annual herb is easily recognized by its finely divided, fern-like leaves, small pink to purple flowers, and distinctive long, beak-like seed pods that coil as they dry. It thrives in dry, open areas such as grasslands, roadsides, and disturbed soils. Historically, alfilaria has been used as forage for livestock and, in some regions, as a minor medicinal or edible plant due to its mild, herbaceous qualities.

Risks & Threats
Alfilaria is naturalized on Kauaʻi, Oʻahu, Molokaʻi, Maui, and Hawaiʻi Island, and possesses traits that are cause for concern. It produces abundant seeds that readily disperse and establish in disturbed environments, allowing it to spread quickly and form dense ground cover. This can outcompete native vegetation, alter soil conditions, and contribute to changes in plant community structure. Its ability to thrive in dry, nutrient-poor soils makes it especially problematic in fragile ecosystems. Because it is well adapted to tropical and subtropical climates, Erodium cicutarium could detrimentally impact tropical island ecosystems.

High Risk Traits:

• Elevation range exceeds 3000 m, demonstrating environmental versatility
  
• Broad climate suitability
  
• Naturalized in regions with tropical climates
  
• Widely naturalized
  
• Crop weed
  
• Environmental weed (reduces biodiversity)
  
• Other Erodium species are invasive
  
• Alternate host of crop pests and pathogens
  
• Dead plants contribute to fuel loads and may increase fire risk
  
• Tolerates many soil types
  
• Forms dense cover
  
• Reproduces by seeds
  
• Self-fertile
  
• Plants are sexually mature 2 to 4 months
  
• Seeds dispersed by explosive separation of mericarp, by water, as a field contaminant and externally by clinging to the fur, feathers, and feet of animals, and the shoes and clothing of people
  
• Forms a persistent seed bank

Low Risk Traits:

• Unarmed (no spines, thorns or burrs)
  
• Palatable to livestock
  
• Shade-intolerant
  
• Not reported to spread vegetatively
  
• Herbicides provide effective control
  
• Fire and mechanical methods may provide effective control