Wild Parsnip

Poison hemlock (Conium maculatum) is among the most deadly plants in North America.  This non-native invasive weed contains highly toxic piperidine alkaloid compounds, including coniine and gamma-coniceine, which cause respiratory failure and death when ingested by mammals.  The roots are more toxic than the leaves and stems; however, all parts of the plant including the seeds should be considered dangerous.  It is a common misconception that poison hemlock sap will cause skin rashes and blisters.  In fact, poison hemlock toxins must be ingested or enter through the eyes, cuts, or...

Wild parsnip (Pastinaca sativa) plants are rising towards their full height and blooms are beginning to appear in southern Ohio.  Landscape managers and gardeners should exercise extreme caution around this non-native invasive plant; the plant's juices can cause phytophotodermatitis (a.k.a. Berloque dermatitis).   If plant juices contact skin and the skin is then exposed to sunlight (specifically ultraviolet light), severe blistering can occur, as well as skin discoloration that may last several months. 

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