Entry #120

Acorn Production Patterns Across Six Years in Oregon White Oaks Emily Sedgewick, Gareth Hopkins, Ava Howard Oak Ecology Research Group, Western Oregon University, Monmouth, Oregon 97361 Oregon white oaks (Quercus garryana) are an essential part of local ecosystems due to the environment and food it provides to wildlife. Loss of oak woodlands and savannas has made collections of acorns essential to restoration efforts. Oaks experience masting years, during which they generate a large number of acorns interspersed among low production years. To understand variation in reproduction, we collected acorns yearly in the fall from up to 64 oaks from 2019-2024. We used ten-minute time-constrained searches beneath each tree’s canopy. Trees in savanna grazed by cows produced more acorns than trees in all other habitats. Masting events occurred in 2019, 2021, and 2023. Previously published literature documents masting on a four-year cycle; three years of low reproduction followed by a spike in acorn reproduction in the fourth year. Our data contradicts this, with a spike in acorn reproduction documented in 2021 that occurred two years after a mast year in 2019. As Oregon white oak populations continue to decline, further understanding masting behavior of these trees is essential for effective restoration. Keywords: Masting, Quercus garryana, White oak, Habitat