Abstract: Studies on the fire resistance of small and medium-sized shrubs in landscape plant community can guide the evidence-based landscape design and fire prevention when managing and constructing urban green spaces. In this study, four components of plant flammability of 10 landscape shrub species in Beijing were measured under varying moisture conditions in both winter and spring. We used principal component analysis combined with a comprehensive evaluation based on the entropy weight method to measure fire resistance under assumed heat radiation conditions. The canopy structure of individual species was taken into account. There was a significant correlation between the canopy fire resistance rank and twig fire resistance rank across the 10 shrub species, with a correlation coefficient of 0.867, predominantly related to combustibility. Among the four components of plant flammability, there was a significant correlation between the ranks of ignitability-fire resistance and consumability-fire resistance, with a correlation coefficient of -0.794. The relative fire resistances of the 10 shrub species in a descending order were: Cotoneaster horizontalis > Syringa oblata > Lonicera maackii > Weigela florida > Kerria japonica > Hibiscus syriacus > Forsythia suspense > Lagerstroemia indica > Kolkwitzia amabilis > Jasminum nudiflorum. Our results demonstrated that Cotoneaster horizontalis and Syringa oblata were the most suitable species among the 10 examined species for fire prevention when planning the construction and management of urban green spaces. City planners should be aware of the relatively poor fire resistance and low ignition threshold of Lagerstroemia indica.

Key words: landscape shrub, flammability, fire resistance, cone calorimeter, urban green space.