POISON OAK

Leaves

• “Leaves of three, let it be” — always in clusters of 3

• Middle leaf has a longer stem; side leaves are shorter

• Edges are often lobed or wavy (can resemble oak leaves, but not always)

• Surface can be shiny or dull

• Color changes by season:

  • Spring: bright green or reddish

  • Summer: green

  • Fall: red/orange

Growth Pattern

• Grows as a:

  • Low shrub (most common in California)

  • Climbing vine (on trees, fences, etc.)

• Vines often look hairy or fuzzy

Other Clues

• May have small white or greenish berries

• Stems can be reddish

• Commonly found:

  • Along trails

  • Near shaded areas, creeks, hillsides

Important

• The oil (urushiol) causes the rash

• Can spread via:

  • Direct contact

  • Clothing or gear

  • Pets that brushed against it

Quick Field Rule

If it has:

• 3 leaves

• Lobed or wavy edges

• Shrub or hairy vine growth

Assume it’s poison oak and avoid it.