Enviro News Asia, Jakarta – Indonesia’s National Research and Innovation Agency (BRIN) highlighted the biological defense mechanisms that enable trees to survive injuries and decay during the Talk about Scientific Collection Series #17 webinar held on July 20.
Kuatman, Junior Expert Analyst for Science and Technology Utilization at BRIN’s Directorate of Scientific Collection Management, explained that trees are dynamic living organisms capable of protecting healthy tissues by isolating damaged or infected areas through a natural defense mechanism known as Compartmentalization of Decay in Trees (CODIT). The model was developed by Dr. Alex L. Shigo in the 1970s.
According to Kuatman, unlike animals, trees cannot repair damaged wood cells. Instead, they compartmentalize infected tissues to prevent the spread of decay caused by pathogens and fungi, allowing new healthy growth to continue.
He explained that wood decay generally begins with mechanical injuries or pruning wounds that expose tree tissues to insects, bacteria, and fungi. As decomposition progresses, trees activate a four-wall defense system that limits the spread of infection within the trunk.
The first wall restricts the vertical movement of pathogens by blocking xylem vessels above and below the wound. The second wall slows inward decay through growth rings rich in lignin, while the third wall provides stronger lateral protection using ray cells that produce antimicrobial compounds. The fourth and strongest barrier is formed by the cambium after injury, creating a protective zone that completely separates infected wood from newly formed healthy tissue.
Kuatman noted that the effectiveness of the CODIT system depends heavily on the tree’s overall health. Trees with sufficient carbohydrate reserves can produce stronger defensive barriers, whereas trees under stress from compacted soil, root oxygen deficiency, or water shortages develop weaker protection that is more susceptible to fungal invasion.
He also outlined three key conservation interventions to improve tree resilience. These include reducing wind stress through selective crown pruning, strengthening vulnerable branches with non-invasive flexible cable systems, and improving root-zone conditions by increasing soil aeration and supporting root health to stimulate new wood formation.
BRIN Director of Scientific Collection Management Sasa Sofyan Munawar said understanding tree defense mechanisms is essential for botanical gardens and institutions responsible for conserving living plant collections. He emphasized that healthy collections serve as valuable ex-situ conservation resources representing Indonesia’s native forest biodiversity and support long-term preservation efforts. (*)
