NOXIOUS PLANTS in the field
A Guide for the Prevention of Injuries due to Noxious Plants
NB: Powerpoint generated by Eastern Region's Geomatics Section for educational and in-house training purposes.
Plant Characteristics (Giant Hogweed)
• Grows 1.5 to 5m, with a large root and thick, hollow stems
• Stems are covered with reddish-purple flecks and stiff hairs filled with sap
• Very coarse, large, and shiny leaves characterized by a serrated edge
Look-a-like : Queen Anne's Lace
• Produces a large cluster of white flowers – however, only flowers once in its lifetime
• Flower clusters can measure up to 1.5 m in diameter (made up of several smaller umbrella-like clusters)
Plant Characteristics (Wild Parsnip)
Stalks of leaves completely encircle the stem
Grows 0.5-1.5m, with a highly branched, hollow stem; smooth appearance with few hairs
Giant Hogweed
Leaves are sharply toothed, relatively broad, and somewhat mitten-shaped
Flowers - supported by a single branch in a flat-topped, umbrella-like yellow clusters
Member of the carrot and parsley family
Does not flower in its first year of growth
Wild Parsnip
• Invasive garden ornamental found across southern and central Ontario
• Varied habitat – roadsides, ditches, streams, and in open fields
• Contain Furocoumarins
• Invasive plant observed in all provinces and territories except Nunavut
• Grows in disturbed areas (roadside ditches, cracks in pavement, fence rows, yards, etc).
• Most prevalent from July-September
• The sap of the plant contains furocoumarins (causes photosensitization and dermatitis)
On today's journey out into the field, we will review strategies for the prevention and treatment of injuries resulting from contact with:
- Poison Ivy
- Poison Sumac
- Wild Parsnip
- Giant Hogweed
Remember, these are NOT the only dangers which reside in the field. It is you and your manager's responsibility to ensure that you are aware of any dangers specific to your work area, and to take necessary precautions to prevent injury.
Furocoumarins
What to Do - URUSHIOL
• Class of plant-produced biochemical compounds which sensitize the skin to the effects of UV light
• Can cause severe skin dermatitis and increase risk of phototoxicity
POISON IVY
Before heading out into the field, workers should be aware of the following basic guidelines for minimizing contact with noxious plants:
- toxicodendron (rhus) radicans L.
- a widespread straggling or woody vine found in every province EXCEPT Newfoundland
- extremely variable habitat (borders off woods, roadsides, deep woods, clearing, sandy, stony, rocky shores, etc)
- contains the poisonous resin URUSHIOL
- all parts of the plant are toxic to humans, except for the flowers, pollen, fruit and pulp
WEAR PPE
BE ABLE TO IDENTIFY NOXIOUS PLANTS
The best way to avoid injuries from NOXIOUS PLANTS is to avoid them!
The best way to do this is to be able to identify them, and any work areas in which they may be present.
Workers should ALWAYS wear PPE (gloves, long clothing, boots and socks) to prevent skin contact with noxious plant sap.
After coming into contact with the oil from a noxious plant, remove as much of the oil from
the skin as possible using absorbent paper (do not spread the oil)-
MAKE SURE YOU WEAR GLOVES TO DO THIS.
Wash the skin in lukewarm, soapy water as soon as possible to
prevent the spread of the oil; ensure that all clothing, tools, and
any other surfaces that may have come into contact are washed thoroughly also
Once contact has been made with the skin, urushiol penetrates rapidly.
The oils from the plant must be completely removed from the skin within 10 minutes to
avoid developing a rash.
Rashes from urushiol form 12 to 48 hours after exposure in those that
have been previously sensitized; for those who react after their first
exposure, the rash may take up to 7 to 10 days
If a rash forms, to dry up blisters and provide relief from itching,
use calamine lotion or oatmeal baths
It is also possible to talk to a health care professional about
obtaining prescription medications which may help
Poison Sumac
URUSHIOL
- Allergic dermatitis (intense itching and redness followed by appearance of papules, bullae or vesicles)
- Edema (swelling caused by excess fluid in the body’s tissues)
- Rarely, urticaria (hives), erythema multiforme (a hypersensitivity reaction) or secondary bacterial infections may result
• Found in southern Ontario and Quebec – uncommon due to wet habitat
• Contains URUSHIOL
• All parts of the plant are toxic to humans except the pollen, anthers, xylem, and epidermis
What about Winter?
Plant Characteristics (Poison Ivy)
Leaves Change Colour with Seasons
Various Heights and Sizes (shrubs, vines)
"Leaflets three - let it be!"
Compound leaves of three pointed leaflets, leaflet edges may be smooth or toothed
Flowers
Plant Characteristics (Poison Sumac)
Because toxins are found in multiple parts of each plant, it is possible to obtain a rash from these plants in the winter, even when the plants have lost all of their leaves.
Workers should use caution when working in an area with noxious plants, even when there is snow on the ground and take precautions to minimize any exposure to them.
greenish-white and yellow blossoms in early summer; white or cream coloured berries in early autumn
Aerial roots along stem (contributes appearance of "fuzzy rope"
What to Do - Furocoumarins
Native tree or deciduous woody shrub which grows in wet areas (roots grow in water) - sparse, open form
Smooth, alternating leaflets arranged in pairs with red rachis (single leaflet at end)
After coming into contact with the oil from a noxious plant,
remove as much of the oil from the skin as possible, using absorbent paper (do not spread the oil) – MAKE SURE THAT YOU WEAR GLOVES TO DO THIS
Wash the skin in lukewarm, soapy water as soon as possible to prevent the spread of the oil; ensure that all clothing, tools, and any other surfaces that may have come into contact are washed thoroughly also
- avoid sunlight
- seek medical help if necessary
Leaves change colour with seasons
Flowers - yellow-green flowers which mature to ivory-white and gray fruits