Mitigating tropical cyclone susceptibility in pecan (Carya illinoinensis) orchards

The production of tree nuts such as almonds, walnuts, pistachios, and pecans is a globally important agricultural industry. Climate risk posed to tree nut orchards was recently brought to light by a series of severe tropical cyclone impacts to the primary pecan-producing areas of Georgia, USA which caused $1.2 billion USD in losses. Understanding how severe wind risk changes with pecan tree size can guide the development of climate-smart practices that improve global resilience of tree nuts. Immediately after 2023 Hurricane Idalia, we reconstructed hurricane damage to 11 pecan orchards across southern Georgia and examined how tree susceptibility varied with wind speed and tree size for 1142 trees. We found that the probability of tropical cyclone damage to pecan trees increased with wind speed and was highest for intermediate size classes—peaking at 35 cm diameter at breast height. We developed a conceptual model for assessing hurricane risk on crop yield which illustrates how explicit consideration of age-structure can influence expected profits when hurricane risk is considered. We recommend that pecan growers consider age and size structure in orchard planning. Prior research also suggests that mechanical hedge pruning increases windfirmness. Climate-smart practices can enhance resilience and sustainability in pecan orchards in future climates where increases in severe tropical cyclones are expected.