Poison-sumac

Silhouette - poison-sumac
  • Latin name: Toxicodendron vernix (L.) Kuntze
  • French name: Sumac à vernis
  • Synonym(s): Swamp-sumac , poison-elderberry , poison-dogwood
  • Taxonomic Serial Number: 28823
    28778 [syn. R. vernix L.]
Description

Leaves

  • Leaf - poison-sumac
  • Leaflet - poison-sumac

Form

  • Deciduous, alternate
  • Pinnately compound
  • 7–13 leaflets
  • Leaflets long-pointed, stalked
  • Lower surface hairless
  • Base wedge-shaped

Length

  • Leaflets 4–8 cm
  • Leaflets and central stalk 15–30 cm

Colour

  • Upper surface lustrous dark green
  • Lower surface whitened
  • Petiole often reddish

Margin

  • Smooth

Buds

  • Lateral bud and leaf scar - poison-sumac

Form

  • Terminal bud conical
  • Lateral buds smaller than the terminal bud
  • Leaf scars broad, shield-shaped, with many dot-like vein scars in 3 loose groups

Length

  • Terminal bud 10–19 mm

Colour

  • Purplish-brown

Twigs

  • Winter twig - poison-sumac

Form

  • Slender, drooping
  • Hairy when young, becoming hairless
  • Lenticels prominent

Colour

  • Dark green becoming mottled, brownish-yellow

Flowers

Form

  • Small
  • Open, drooping, branched auxiliary clusters (panicles)

Colour

  • Yellowish

Structure

  • Dioecious

Fruits

  • Fruit cluster - poison-sumac

Form

  • Small, rounded, berry-like
  • Hairless, 1-seeded, thin-fleshed
  • In loose, drooping clusters
  • Usually remain on the tree throughout winter

Width

  • 10–13 mm

Colour

  • Glossy white or ivory

Structure

  • Drupe

Bark

Form

  • Smooth

Colour

  • Light grey

Size

Height

  • To 6 m

Diameter

  • To 10 cm

Tree form

  • Silhouette - poison-sumac

Forest-grown

Trunk

  • Slender

Crown

  • Small, rounded

 

Habitat

Site

  • Open, swampy woodlands

Associated species

  • Willows, black ash, white elm, silver maple, and eastern white-cedar

Range

Rare in Canada; southern Ontario and Quebec

Photos
  • Poison-sumac
Distribution map
Distribution map - poison-sumac
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