Family: Amaranthaceae

Origin, Description & Uses
Ptilotus nobilis, commonly known as lamb’s tail, regal foxtail, or tall mulla mulla, is a striking ornamental plant native to Australia. It is admired for its tall, feathery flower spikes that range from silvery pink to purple and bloom over a long season. This drought-tolerant species thrives in sunny, well-drained conditions and is well suited to dry gardens, xeriscapes, and container plantings. Its unusual texture and colorful flower plumes make it popular in ornamental landscaping, pollinator gardens, and fresh or dried floral arrangements.

Risks & Threats
This species is considered low risk for Hawai‘i and other tropical island environments. Ptilotus nobilis is primarily cultivated as an ornamental and has not shown significant tendencies to spread aggressively or invade natural ecosystems. As with many garden plants, it may occasionally reseed in favorable conditions, but it is not known to form dense infestations or displace native vegetation. Using responsible gardening practices, such as monitoring for unwanted seedlings and preventing garden waste from spreading into natural areas, can help ensure this attractive species remains a safe landscaping choice.

High Risk Traits:

• Broad climate suitability
  
• Grows in tropical climates
  
• Tolerates many soil types
  
• May form dense stands within native range (unknown if able to exclude other vegetation)
  
• Reproduces by seeds
  
• Able to reach maturity in <1 year
  
• Seeds dispersed by wind and intentionally by people
  
• Gaps in biological and ecological information may reduce accuracy of risk prediction

Low Risk Traits:

• No reports of invasiveness or naturalization, but unclear if widely introduced outside native range
  
• Unarmed (no spines, thorns or burrs)
  
• Provides fodder for livestock
  
• Ornamental
  
• Not reported to spread vegetatively
  
• Seed viability may be low