Fight fire with food forests: Assessing flammability of tropical crop plant species to design fire-smart agroforestry systems.

Premise: The increased frequency of droughts and wildfires in recent decades poses a significant risk to agricultural lands and private property. Given the negative impact of fires on food production and associated livelihoods, it is crucial to assess the flammability of crop species and find ways of mitigating risk of fire in agricultural lands.

Methods: We quantified the shoot-level flammability of 65 tropical species of fiber, food, and spice crops by assessing maximum temperature, burn time, and burnt biomass and assessed key leaf traits from a subset of these species to assess how specific leaf area (SLA), leaf area (LA), and leaf dry mass to fresh mass ratio (DM:FM) influences these flammability measures.

Results: Groundcover, shrubs, and vines were generally less flammable than canopy and subcanopy plants. DM:FM was a consistent and significant predictor of all three flammability measures regardless of plant life form.

Conclusions: Our results equip farmers and policymakers with information to construct agricultural landscapes that are more fire resilient and options for pursuing nature-based solutions to mitigate fire risk, such as planting green firebreaks with fire-retardant species.