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Kowhai is rated fire resistant, though that conclusion rests on limited laboratory evidence rather than field performance.
On Fire and Emergency New Zealand's seven-level scale, kowhai is classed as low flammability, one step above very low. Its directory also flags the tree as poisonous, a separate concern that does not change the flammability classification. A 2016 study in the International Journal of Wildland Fire likewise assigned kowhai shoots to its low-flammability cluster after samples were air-dried for 24 hours before testing.
With branches dried before testing on a grill, the measured ignition frequency was 40 percent. The global FLAMITS database preserves that number as an ignitability measurement but does not set a common threshold that turns unlike laboratory measurements into resistant or hazardous verdicts. The figure therefore adds context without overturning or independently confirming the two low-flammability classifications.
Kowhai, or Sophora microphylla, is a tree in the Fabaceae family. The practical reading is reassuring but narrow: laboratory tests place its shoots in a low-flammability category, supporting a fire-resistant rating, while the evidence does not establish how an entire tree will behave in every garden or fire.
Form
tree
Region
New Zealand
Rated in
Global; New Zealand
Uses
ornamental
On this lot
1. Fire evidence and conditions
Fire evidence
Fire-resistant — location does not change the cited classification.
Fire-performance conditions
Fire ecology context
Placement evidence
Evidence regions
Global; New Zealand
Maintenance
2. Why this plant is relevant here
State distribution
Native range
Introduced / established
USDA hardiness
3. Legal, ecological, and broader status
Legal-list status
Seed-list status
Reported invasive here
Broader regional context
Federal context
How to read this page
The status above is computed from the cited rows below: independent recommendations can support a fire-resistant result, an avoid row can produce keep-away, and disagreement stays visible as conflict. Placement notes preserve each source’s own scheme rather than translating unlike rules into one scale. This is evidence about a plant, not permission to plant it in every part of the defensible space; Zone 0 remains noncombustible.
The evidence
Grouped by what each source concluded. Primary evidence rated the plant itself
(a lab, field program, or original curation); corroboration compiled or
republished another source's rating and resolves to its root lineage.
Recommends (2)
Low Flammability Plants directory — Fire and Emergency New Zealand (plant flammability testing at Lincoln University) · 2026 · original sourcePrimary evidenceLab-testedlineage: lincoln-nz-tree
“Low flammability”
Low flammability classification. Flagged poisonous in the FENZ directory.
8 cited rows from this source; its identity, lineage and tier are stated once.
Primary study Cui2020a: Cui, X., Paterson, A. M., Wyse, S. V., Alam, M. A., Maurin, K. J. L., Pieper, R., ... Curran, T. J. (2020a). Shoot flammability of vascular plants is phylogenetically conserved and related to habitat fire-proneness and growth form. Nature Plants, 6, 355-359.
Shared row context: plant part branches; fuel all; predrying yes; device grill; site Cui2020a-1; sampling ND.
“ignition frequency (%): 40”
FLAMITS record 1504; Ignitability measurement.
“maximum sample temperature (°C): 225.6”
FLAMITS record 1698; Combustibility measurement.
“burning duration (s): 2.3”
FLAMITS record 1892; Sustainability measurement.
“estimated burnt biomass (%): 10.5”
FLAMITS record 2086; Consumability measurement.
Primary study Wyse2016: Wyse, S. V., Perry, G. L. W., O'Connell, D. M., Holland, P. S., Wright, M. J., Hosted, C. L., ... Curran, T. J. (2016). A quantitative assessment of shoot flammability for 60 tree and shrub species supports rankings based on expert opinion. International Journal of Wildland Fire, 25, 466-477.
Shared row context: plant part branches; fuel all; predrying yes; device grill; site Wyse2016-3; sampling ND.
