Family: Lauraceae
Cinnamomum camphora, commonly known as the camphor tree, is a large evergreen tree native to Japan, Korea, the Nansei-shoto (Ryukyu Islands), and Taiwan. It is easily identified by its broad, spreading canopy, glossy green leaves, and the strong camphor scent released when the leaves or bark are crushed. Historically valued as a source of camphor oil for medicinal, industrial, and fragrance uses, the camphor tree has also been widely planted as an ornamental and shade tree. In Hawaiʻi, it has escaped cultivation and is now naturalized on Kauaʻi, Oʻahu, and Maui, with populations on Molokaʻi that appear to be in the early stages of naturalization.
In the Hawaiian Islands, camphor tree can spread readily into surrounding landscapes through bird-dispersed seeds, allowing it to establish dense stands that shade out native plants and alter forest structure. Its aromatic leaf litter and chemical compounds may affect soil conditions, making it harder for native species to regenerate. The tree’s large size, longevity, and ability to resprout after cutting make it difficult to manage once established. Preventing further planting and carefully managing existing trees near natural areas can help limit its continued spread and ecological impacts in Hawaiʻi.
High Risk Traits:
- Naturalized/invasive in multiple regions (Florida, Australia, Hawaii, South Africa)
- Broad climate suitability (tropical/subtropical, USDA zones 8–11)
- Tolerates wide range of soils, including saline
- Environmental and agricultural weed (forms dense stands, reduces pasture productivity)
- Toxic to animals and humans (ingestion can be fatal)
- Seeds dispersed by birds and water
- Can spread vegetatively from root sprouts
- History of repeated introductions as an ornamental
- Forms dense thickets that suppress native regeneration
Low Risk Traits:
- Short-lived seed bank (viability <1 year)
- Not a prolific seed producer
- Can be controlled with herbicides
- Requires full light as mature tree (not a deep shade plant)
