Awards issued prior to january 20, 2025, were funded under previous administrations and may not reflect the priorities and policies of the current administration.** fires have considerable impacts…

Awards issued prior to january 20, 2025, were funded under previous administrations and may not reflect the priorities and policies of the current administration.** fires have considerable impacts on the mortality and post-fire growth of many important timber species. However, the mechanistic causes of tree death in pines remains uncertain and limited studies have focused on how the fire impacts the productivity of fire-affected surviving trees. Information is also lacking on whether mitigation approaches, such as fertilizer, can be used to give the trees more resistance to the fire and help them recover faster. We address these knowledge gaps through two central hypotheses. The first seeks to assess whether fire-induced mortality is due to phloem and cambial death, soil nutrient deficiencies, emboli induced hydraulic failure, or pre-fire structural overshoot. The second seeks to characterize the relationship between the fire intensity and the post-fire productivity and assess whether nonstructural carbohydrate and nitrogen reserves act to help the trees recover faster. The project has four supporting objectives: 1) assess mechanisms of fire-induced mortality in saplings of selected pinus species; 2) determine the 'fire intensity' dose to mortality and productivity responses' for the saplings of different eight pinus species; 3) determine how these relationships change when the saplings have been treated with supplemental nitrogen before and immediately after the fires; and 4) share data and results with forest productivity and fire effects modeling teams. This project is directly aligned with the goals of the program as IT assesses sapling growth, carbon assimilation, mechanisms of sapling response to stress from fire, and the utilization of supplemental nitrogen.