2.2 Sap flow, cambium vitality, moisture status

Tree Physiological Readiness: Sap Flow, Cambium Vitality & Moisture Status – Ensuring Success in Agarwood Resin Induction

Successful agarwood induction requires healthy, responsive trees. Beyond DBH and age, three physiological indicators determine whether a tree can tolerate induction and produce quality resin:

  1. Sap Flow – measures nutrient and water circulation
  2. Cambium Vitality – indicates active growth potential
  3. Moisture Status – ensures proper stress-response capacity

1. Sap Flow: The Circulatory System of the Tree

Why It Matters

  • Supplies water and nutrients to injured sites
  • Carries stress signals and defense molecules
  • Ensures resin precursors reach the induction zone

Field Indicators

  • Healthy trees exude sap slowly when bark is wounded
  • Morning sap flow should be visible but not excessive
  • Absence of sap may indicate stress or disease

BarIno™ Implication

  • Low sap flow → delay inoculation
  • High sap flow → tree ready for AgarStart™ or FusaPrime™

Field Check

  • Make a small, shallow cut at the intended injection site
  • Observe sap color (clear/light brown) and rate (steady, not dripping)

2. Cambium Vitality: Growth Potential

Why It Matters

  • The cambium is a thin layer of living cells between bark and xylem
  • Active cambium ensures:
    • Rapid wound healing
    • Effective resin production
    • Long-term tree survival

Field Indicators

  • Bark is elastic, not brittle
  • Green layer under bark when scratched
  • No dry or dead patches along the trunk

BarIno™ Implication

  • Dormant or dead cambium → poor resin formation
  • Active cambium → tree ready for all induction phases

Field Check

  • Remove a small piece of bark at DBH level
  • Look for bright green cambial layer
  • Avoid areas with dark or brown cambium

3. Moisture Status: Hydration for Defense

Why It Matters

  • Adequate water allows the tree to:
    • Respond to stress signals
    • Maintain resin synthesis
  • Excessive water or drought compromises defense and increases mortality risk

Field Indicators

  • Soil is moist but well-drained
  • Tree shows no leaf wilting
  • Twigs are flexible, not brittle

BarIno™ Implication

  • Dry soil → avoid induction (risk of tree collapse)
  • Waterlogged soil → risk of fungal overgrowth or infection

Field Check

  • Dig ~10 cm around base; soil should be damp, not dry
  • Check for leaf turgidity and twig flexibility

4. Integrated Tree Readiness Assessment

IndicatorGoodCautionAction
Sap FlowSteady, light brownVery low or too highDelay or adjust induction
CambiumBright green, elasticBrown, brittle, patchyDelay induction
MoistureSoil damp, leaves turgidDry or waterloggedIrrigate / wait for optimal conditions

5. BarIno™ Principle

A tree must be physiologically ready before any inoculation.
Sap flow, cambium vitality, and moisture status are your most reliable field indicators.