The Fire and Tree Mortality Database, for empirical modeling of individual tree mortality after fire.

Wildland fires have a multitude of ecological effects in forests, woodlands, and savannas across the globe. A major focus of past research has been on tree mortality from fire, as trees provide a vast range of biological services. We assembled a database of individual-tree records from prescribed fires and wildfires in the United States. The Fire and Tree Mortality (FTM) database includes records from 164,293 individual trees with records of fire injury (crown scorch, bole char, etc.), tree diameter, and either mortality or top-kill up to ten years post-fire. Data span 142 species and 62 genera, from 409 fires occurring from 1981-2016. Additional variables such as insect attack are included when available. The FTM database can be used to evaluate individual fire-caused mortality models for pre-fire planning and post-fire decision support, to develop improved models, and to explore general patterns of individual fire-induced tree death. The database can also be used to identify knowledge gaps that could be addressed in future research.

Resprouting by seedlings of four North American deciduous broadleaved tree species following experimental burning.

In eastern North American Quercus forests, the historic fire regime, characterized by periodic, low-intensity surface fire, facilitated the development and maintenance of mid-successional Quercus forests across multiple spatial and temporal scales. One physiological mechanism favoring Quercus over mesophytic and/or shade-tolerant deciduous broadleaved species is prolific and vigorous resprouting following topkill. Generalizations regarding interspecific differences in fire-induced resprouting are confounded by interactions between biotic and abiotic factors. The goal of this study was to quantify resprout dynamics by 2- and 3-year-old seedlings of four prominent deciduous broadleaved species (Acer rubrum, Liriodendron tulipifera, Quercus alba, and Q. rubra) following topkill via experimental burning, where seedling age, competition, fire intensity, and light were controlled. Resprouting was independent of fire intensity and seedling size. The resprout rate of Q. rubra (82%) was greater than that of A. rubrum (53%), L. tulipifera (56%), and Q. alba (52%). A second burn conducted a year later did little to inhibit resprouting by topkilled individuals. After both burns, L. tulipifera sprouts were significantly taller than the other species. Although absolute height of Q. rubra sprouts was greater than A. rubrum after the first burn, absolute height of Q. rubra sprouts was lower than A. rubrum following the second burn. Results suggest that broad, cross-genus generalizations may not accurately reflect interspecific differences in resprout potential, which may have implications related to the ability to regenerate and recruit Quercus under a re-introduced periodic fire regime.