Hemlock (Conium maculatum), a toxic Eurasian and North African carrot. AgVic’s public file suggests the plant was deliberately introduced to Australia, however as Hemlock is not included in early Victorian nursery catalogues, the assumption would appear to be that it was brought from Europe on a casual basis to be grown as a traditional medicinal herb. Distributed readily by seed, it is highly possible that it was also introduced (or re-introduced) as a contaminant.
The preferred civic poison of Ancient Greece, Hemlock was first recorded on the banks of the Yarra at Manningham in 1897. Within the metropolitan, the plant remains a weed of degraded floodplains; it has also established extensively in the region around Ballarat and is found in damaged riparian settings throughout the state.