How to Protect Outdoor Workers from Poisonous Plants


Workers who work outside, such as landscapers, farmers, loggers and anyone out in the woods, are exposed to a whole host of safety hazards, from heat stress to insects and wild animals. In fact, even the plants around workers—as pretty as they may be—can be poisonous and causes rashes and serious injuries.


  • A forestry worker was struck in the face with Devil’s Club while collecting field data. She stepped on the prickly shrub and, as she moved her foot, the shrub sprang back and hit her in the side of the face. Two prickles got embedded in her left eye—requiring a 40-minute surgery to remove them.
  • While cutting down giant hogweed, a worker got some sap on his hands. Two days later, his hands were blistered and red. After the blisters cleared, he had dark blotches on his hands for seven months.

According to this guide on poisonous outdoor plants from the Alberta government, most plants won’t bother you if you leave them alone. But if you touch, crush, inhale or eat them, some may produce upsetting, painful or even fatal results.

Certain chemicals on leaf surfaces or in plant juices may be skin irritants and induce reddening, swelling or blistering. Because these potentially irritating chemicals often accumulate in plant organs such as seeds and roots, a small amount of this type of tissue can contain a relatively large amount of toxin.

Plus, plants that aren’t commonly thought of as poisonous can become so if ingested in large quantities, such as onions, chives, beets, Swiss chard, borage, rutabaga, broccoli, Brussels sprouts, cabbage and turnips.

Other plants can cause injuries because of their spines or thorns or when you inhale particles from them.

To protect workers from contact with poisonous plants, ensure that they:

  • Can recognize hazardous plants
  • Are aware of the plants they’re working around
  • Inform co-workers and supervisors if they encounter hazardous plants unexpectedly
  • Wear protective clothing and PPE, such as gloves and long sleeves
  • Avoid touching their eyes or wiping plant sap on other parts of their body or clothes
  • Keep asthma and allergy medications available if they’re sensitive to certain plants
  • Wash immediately with soap and water and seek medical treatment if their skin comes into contact with a toxic plant
  • Flush their eyes immediately with water and seek medical treatment if sap or another part of a poisonous plant gets in them.

And to avoid illness from eating outside vegetation, workers should follow these rules:

  • Avoid eating all plants that have coloured or milky juices, such as members of the milkweed, poison ivy, spurge and poppy families.
  • Fruits you don’t recognize should all be treated as potentially toxic.
  • Avoid all unknown white or red fruits. For example, poison ivy and baneberry have white fruits and are poisonous. Baneberry also has a red-fruited form.
  • Avoid all fruits that are three-sided or three-lobed, including members of the spurge, horse chestnut, lily and amaryllis families.
  • Avoid eating fruits, seeds, roots and tubers of wild plants as the toxicity of plants is generally greatest in storage organs such as these.
  • Avoid all bulbs that don’t smell like onions or garlic. For instance, bulbs from members of the lily and amaryllis families can be fatal if eaten in large quantities.