Arborist Certification Study Guide
🌱 Tree Structure
The three major structural zones of a tree are the roots, trunk, and crown. Each plays a critical role in stability, nutrient movement, and energy production.
Root System
- Absorbs water and nutrients
- Provides anchorage
- Most roots are in the top 18 inches of soil
- Mycorrhizae increase nutrient uptake
Trunk & Vascular System
- Xylem moves water upward
- Phloem moves sugars downward
- Heartwood provides strength
Crown
- Leaves perform photosynthesis
- Branches distribute weight
- Bud arrangement helps identify species
🌿 Growth & Physiology
Trees grow through primary (height) and secondary (diameter) growth. Hormones regulate responses to light, gravity, and injury.
Photosynthesis
- Requires sunlight, CO₂, and water
- Produces sugars for growth
Respiration
- Breaks down sugars for energy
- Occurs day and night
Transpiration
- Water evaporates from leaves
- Creates suction that pulls water upward
🌳 Tree Health
Tree health depends on soil quality, water availability, proper pruning, and protection from pests and diseases.
✂️ Types of Pruning
- Crown cleaning
- Crown thinning
- Crown raising
- Crown reduction
🔪 Cutting Techniques
- 3‑cut method
- Cut outside the branch collar
- Never flush cut
🗓 Best Timing
- Most pruning: dormant season
- Flowering trees: after bloom
🪢 Climbing Gear
- Saddle
- Climbing line
- Flipline
- Carabiners
- Ascenders & descenders
🧗 Climbing Techniques
- Footlocking
- Body thrust
- SRT & DRT systems
⚙️ Rigging Systems
- Blocks & pulleys
- Friction devices
- Load control
🪖 PPE
- Helmet
- Eye protection
- Hearing protection
- Chainsaw chaps
🪓 Chainsaw Safety
- Two‑handed grip
- Kickback zone awareness
- Chain brake use
🚧 Jobsite Safety
- Communication
- Drop zones
- Traffic control
🍃 Leaf Identification
- Simple vs compound
- Opposite vs alternate
- Margins: serrated, lobed, entire
🌲 Bark Identification
- Color
- Texture
- Pattern
🌳 Growth Form
- Columnar
- Vase‑shaped
- Weeping
🧱 Soil Types
- Sand
- Silt
- Clay
- Loam
🧪 Soil Chemistry
- pH
- Nutrient availability
- Cation exchange capacity
💧 Water Movement
- Infiltration
- Percolation
- Drainage
🐛 Insects
- Borers
- Aphids
- Scale
🦠 Diseases
- Fungal
- Bacterial
- Viral
🧰 Management
- IPM strategies
- Monitoring
- Thresholds
⚠️ Structural Defects
- Cracks
- Included bark
- Decay
🎯 Targets
- People
- Property
- Infrastructure
🛠 Mitigation
- Pruning
- Cabling & bracing
- Removal
📜 Laws
- Local tree ordinances
- Protected species
- Permit requirements
🤝 Ethics
- Honesty with clients
- Tree preservation first
- Safety over profit
🏆 Best Practices
- ANSI A300 standards
- ISA Code of Ethics
- Industry consensus