Family: Rubiaceae
Coffea arabica (wild coffee, Arabian coffee, arabica coffee) is a small evergreen tree or large shrub native to the highlands of Ethiopia and surrounding regions of eastern Africa. It is best known as the primary source of arabica coffee, prized worldwide for its smooth flavor and aroma. The plant has glossy, dark green leaves, clusters of fragrant white flowers, and red berries (“coffee cherries”) that contain the seeds processed into coffee beans. In Hawaiʻi and other tropical regions, cultivated coffee is an important agricultural crop, supporting local farms, cultural traditions, and rural economies. When grown and managed in agricultural settings, coffee can continue to be safely and responsibly cultivated.
Outside of cultivation, however, wild coffee plants can become invasive, spreading into surrounding forests and disturbed areas where they may compete with native vegetation. Wild or unmanaged coffee plants can also harbor plant pests and pathogens, including those that pose a risk to commercially grown coffee crops. These unmanaged populations can act as reservoirs for diseases or insects, increasing the likelihood of spread into nearby farms. For this reason, wild coffee should be actively managed or removed in areas where commercial coffee is grown to protect crop health and productivity. Preventing escape from cultivation and controlling feral plants helps ensure that coffee remains a sustainable and valuable agricultural crop without increasing ecological or agricultural risks.
High Risk Traits:
- Broad climate suitability (elevation range exceeds 1000 m in native range)
- Thrives in tropical climates
- Naturalized on all of the main Hawaiian islands except Ni'ihau; widely cultivated and naturalized elsewhere
- Wild coffee is an environmental weed in Australia, and the Hawaiian Islands, where it threatens several native, endangered plant species
- Aqueous extracts of leaves, stems, and roots exhibit allelopathic properties
- Wild coffee may host pests and pathogens of commercial coffee, and other plants
- Shade tolerant
- Forms dense stands that exclude other vegetation
- Reproduces by seeds
- Hybridizes with Coffea liberica
- Autogamous and self-compatible
- Reaches maturity in 3-4 years
- Seeds dispersed by birds, mammals, and intentionally cultivated by people
- Occurrence along streams suggests water may also disperse seeds
- Able to resprout from cut stumps (unless treated with herbicide)
Low Risk Traits:
- Commercial coffee is an important economic crop. Active cultivation and management can minimize risk of invasiveness
- Unarmed (no spines, thorns, or burrs)
- Not reported to spread vegetatively
- Seeds reported to lose viability quickly if not stored properly
- Herbicides may provide effective control
