7 poisonous plants

Rhus radicans

Poisonous to the touch, this plant has three leaflets that vary in size and shape, from jagged to round edges. It's often mistaken for poison oak. Growing in southern Canada, poison ivy can flourish in rocky areas, even to the point of carpeting the terrain. It can be found growing as a vine on trees and as a large or low shrub.

Poison ivy is a compound leaf plant that causes a skin rash (or severe oozing and a fever in extreme cases). Most potent in spring, it grows white, hard berries in the fall and remains poisonous all year—don’t touch the bare branches in winter.

First aid tips: If your skin is exposed to the plant’s oil, a reaction can take 12 hours to two days to develop. The oil can also stay on your clothes and furniture for days if they remain unwashed, which can result in more delayed reactions.

For relief: take an oatmeal bath, apply a cool compress to the affected skin, or take over-the-counter itch medication. If the irritation doesn’t heal or becomes severe, see a doctor.