Certified Arborist Test Diagnosis and Treatment 4 — Questions and Answers
Question 1: A tree exhibits chlorosis (yellowing) only on new growth while older leaves remain green. Which nutrient deficiency is most likely?
- Nitrogen
- Potassium
- Iron (Correct answer)
- Phosphorus
Correct answer: Iron
Iron deficiency causes interveinal chlorosis on new growth first because iron is immobile in the plant. Nitrogen deficiency, by contrast, affects older leaves first since nitrogen is mobile.
Question 2: What is the recommended approach for treating a tree with bacterial wetwood (slime flux)?
- Install a drain tube to release pressure
- Remove affected branches and apply wound dressing
- No treatment is typically recommended; maintain overall tree health (Correct answer)
- Apply systemic antibiotics via trunk injection
Correct answer: No treatment is typically recommended; maintain overall tree health
There is no effective cure for bacterial wetwood. The current best practice is to maintain overall tree vigor through proper watering, mulching, and fertilization. Drain tubes are no longer recommended.
Question 3: Which diagnostic tool uses sound waves to detect internal decay in trees?
- Resistograph
- Sonic tomograph (Correct answer)
- pH meter
- Refractometer
Correct answer: Sonic tomograph
Sonic (acoustic) tomography sends sound waves through the trunk and measures their speed. Decayed wood transmits sound more slowly, creating a map of internal condition.
Question 4: A tree has mushroom fruiting bodies at its base. What does this most likely indicate?
- The tree is healthy and well-nourished
- Root or butt rot caused by wood-decay fungi (Correct answer)
- Normal mycorrhizal activity
- The tree needs more water
Correct answer: Root or butt rot caused by wood-decay fungi
Mushrooms at the base of a tree typically indicate wood-decay fungi decomposing root or trunk wood. This can severely compromise structural integrity and indicates advanced decay.
Question 5: When treating a tree for nutrient deficiency, which application method provides the fastest response?
- Soil amendment
- Foliar spray (Correct answer)
- Deep root fertilization
- Mulch application
Correct answer: Foliar spray
Foliar sprays deliver nutrients directly to leaf tissue and are absorbed quickly, providing the fastest visual response. However, the effects are temporary compared to soil-based treatments.
Question 6: What is the significance of a cavity in a tree trunk that holds water?
- It provides beneficial moisture to the tree
- It accelerates internal decay and should be drained (Correct answer)
- It indicates the tree has sealed the wound successfully
- It has no significance for tree health
Correct answer: It accelerates internal decay and should be drained
Water-holding cavities promote continued decay by maintaining moisture that supports fungal growth. While drilling drain holes was once common, current practice focuses on overall risk assessment rather than cavity treatment.
Certified Arborist Test Diagnosis and Treatment 4
A tree exhibits chlorosis (yellowing) only on new growth while older leaves remain green.
Which nutrient deficiency is most likely?