Family: Poaceae
Coix lacryma-jobi (Job’s tears) is a robust, perennial grass native to tropical Asia from India to peninsular Malaysia. It has been widely introduced elsewhere and has become naturalized throughout the tropics and subtropics about 22°N and S, including the Hawaiian Islands of Kauai, Oahu, Molokai, Maui, and Hawaii. Although valued as an ornamental and food plant in some locations, it can form dense stands in riparian areas, and may compete with and suppress native plants and other desirable vegetation.
High Risk Traits:
- Thrives and spreads in regions with tropical climates
- Naturalized on Kauai, Oahu, Molokai, Maui, and Hawaii (Hawaiian Islands) and widely naturalized in the wet tropics
- A weed of riparian areas that may negatively impacts certain native vegetation and agricultural crops
- Tolerates many soil types (not substrate limited)
- Reproduces by seeds and vegetatively by rhizome fragments.
- Hybridizes with other Coix species.
- Self-fertile
- Capable of reaching maturity in <1 year.
- Seeds and rhizome fragments dispersed by water, and through intentional cultivation.
- Seeds may also be dispersed by birds, and possibly other animals.
- Tolerates and resprouts after grazing and cutting.
Low Risk Traits:
- An agricultural crop with an ancient, domesticated variety that may be less invasive than the wild type.
- Unarmed (no spines, thorns, or burrs)
- Palatable and used as a fodder plant.
- Non-toxic
- Grows well in high light environments (dense shade may inhibit spread)
- Herbicides may provide effective control if needed.
