Measuring flammability of crops, pastures, fruit trees, and weeds: A novel tool to fight wildfires in agricultural landscapes

"Measuring flammability of crops, pastures, fruit trees, and weeds: A novel tool to fight wildfires in agricultural landscapes"

This open access article was published October 5, 2023, in Science of the Total Environment . Access the article via the permanent web address (DOI). (https://doi.org/10.1016/j.scitotenv.2023.167489)

Abstract

Fires on agricultural land account for 8–11 % of the total number of fires that occur globally. These fires burn through various crops, pastures, and native vegetation on farms, causing economic and environmental losses. Fire management on farms will be aided by understanding the flammability of plant species as this would allow the design of low-flammability agricultural landscapes, but flammability data on large numbers of agricultural species are lacking. Many crop and vegetable species are assumed to be low in flammability, but this has rarely been tested. Therefore, we examined the shoot and whole-plant flammability of 47 plant taxa commonly grown on farms in Canterbury, New Zealand, which included many globally common temperate agricultural crops. We demonstrated that most of the agricultural species were low to very low in flammability, with many of them (24 taxa; 51 %) not igniting in the experimental burning. Among different crop types, fruit crops and cereals had significantly higher flammability, while taxa categorized as vegetable crops, grazing herbs, pasture grasses, pasture legumes, and weeds were lower in flammability. We further showed that taxa with lower moisture content, higher retention of dead material and faster moisture loss rates were higher in flammability. The strong variation of flammability between the studied taxa suggests that the selection of suitable low flammability species and strategic redesign of agricultural landscapes with fire-retardant planting can be a useful tool to reduce fire hazards and impacts of wildfires in agricultural landscapes.

Conclusion

Our study has compared the flammability of plant species commonly found in a temperate agricultural landscape and shows how knowledge of plant flammability can be applied to assess fire hazards and used to design landscapes to combat wildfire. By categorising the flammability of agricultural plant species, this study will enable farmers and landholders to redesign their farms, wherein they may be able to plant any low-flammability species, in areas they deem as high fire hazards. Overall, this knowledge will improve our understanding of the temporal and spatial variation of fire spread and intensity in agricultural landscapes and help prepare for wildfires in the age of rapid global climate change.

Citation

Tanmayi Pagadala, Md Azharul Alam, Thomas M.R. Maxwell, Timothy J. Curran, Measuring flammability of crops, pastures, fruit trees, and weeds: A novel tool to fight wildfires in agricultural landscapes, Science of The Total Environment, Volume 906, 2024, 167489, ISSN 0048-9697