Trichoderma species
The aggressive green colonizer of soaked wood
What it tells you about the building
Trichoderma is a fast, aggressive colonizer of very wet cellulose, common in flood aftermath and chronically wet crawl spaces. Some species are notable for degrading wood and even attacking other fungi — a sign of a mature, wet microbial ecosystem.
Why it matters in assessments
Trichoderma viride appears among the HERTSMI-2 marker species. Its presence in dust at meaningful levels indicates genuinely wet building materials somewhere in the envelope and belongs in the investigate-seriously category.
What remediation requires
Locate the saturation zone — crawl spaces and post-flood assemblies lead the list — remove colonized materials, dry the structure with verification, and address the bulk-water pathway that created the conditions.
Fast-spreading colonies that begin white and turn vivid green as spores mature, often with a coconut-like odor.
- Saturated lumber and subfloor
- Wet drywall and insulation
- Crawl space framing
- Water-damaged paper and cardboard
State editions
Where this species shows up depends on where local climate and housing stock meet its moisture requirement. Read the local picture:
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