Family: Papaveraceae

Mexican poppy is a prickly, yellow-flowered plant originally from Mexico and the southwestern United States. It produces bright yellow blooms and spiny leaves that make it easy to recognize, but also unpleasant to handle. The plant thrives in disturbed areas such as roadsides, pastures, and dry open lands, where it can spread quickly and form dense patches that crowd out native plants.

This species produces toxic sap that can be harmful to people and livestock if ingested. In Hawaii, Mexican poppy has naturalized on several islands, especially in dry lowland areas. Because of its aggressive growth and ability to dominate disturbed habitats, it is considered a nuisance weed and is not recommended for planting. Instead, gardeners are encouraged to choose native or non-invasive ornamentals that provide color without causing harm to Hawaii’s ecosystems.

High Risk Traits:

• Broad elevation range
  
• Widely naturalized
  
• Agricultural weed
  
• Spiny
  
• Unpalatable to animals
  
• Toxic to animals and humans
  
• Tolerates many soil types
  
• Can hybridize with Argemone glauca, Hawaiian poppy
  
• Self-compatible
  
• Annual life cycle
  
• Numerous small seeds dispersed accidentally by animals and humans, and as a contaminant of animal feed and hay
  
• Forms a persistent seed bank

Low Risk Traits:

• Shade-intolerant
  
• Medicinal uses
  
• Herbicides provide effective control
  
• May be controlled with proper cultivation practices