Previous Steps

• 1b – Alternate leaf arrangement on stem — go to 18
  • 18a – Leaf simple — go to 19
    • 19b – Thornless — go to 22
      • 22e – All leaves unlobed — go to 31
        • 31d – Leaf is oval or oblong (twice as long as wide) — go to 40
          • 40a – Leaf base asymmetrical — go to 41

Current Step

• 41a – 1-3 main veins. Irregular venation. Leaf 2-3 time longer than width. Pith chambered — Common Hackberry

• 41b – 3-5 main veins. Heart-shaped base on some leaves. Leaf almost as wide as long. Solid pith — Linden

• 41c – 1 main vein — go to 42

Resources

• Identifying Broadleaf Flowering Trees and Shrubs, CMG GardenNotes #173
• List of trees in this key
• Glossary of Terms
• Front Range Tree Recommendation List
• Online CSU Extension publications on Tree and Shrub Selection