Family: Euphorbiaceae
High Risk Traits:
- Grows in temperate and Mediterranean climates
- Naturalized in North America, and elsewhere, but no evidence in the Hawaiian Island to date
- A garden weed due to its ability to spread, and its toxic sap making removal hazardous
- A potential pasture weed that may reduce forage due to toxic properties
- An environmental weed in North America that competes with native and desirable vegetation
- Other Euphorbia species are invasive weeds
- Unpalatable to browsing and grazing animals (due to toxic sap)
- Sap toxic to humans and animals
- Tolerates many soil types
- Reproduces by seeds and vegetatively by root fragments
- Reaches maturity in two growing seasons (biennial)
- Seeds dispersed by explosive dehiscence, by mowing equipment, by water, possibly by birds, by ants, and through intentional cultivation
- Seeds may form a persistent seed bank (up to 8 years)
- Tolerates cutting and mowing (resprouts from roots)
Low Risk Traits:
- May only be invasive at cooler, higher elevations in tropical island ecosystems
- Unarmed (no spines, thorns, or burrs)
- Grows best in high light environments (dense shade may inhibit spread)
- Herbicides may provide effective control