High acorn predation limits assisted regeneration in Mediterranean oak woodlands.
Antoniella G, Capizzi D, Calò A, Corsanici R, Cimini D
Seed Saving
If you've ever tried direct-seeding oaks in a restoration planting or food forest only to find them all gone within a week, this study names the culprits — jays by day, mice by night — and explains why your burial depth and planting spot matter more than you might think.
Researchers planted nearly 1,800 acorns from four oak species in an Italian woodland and watched what happened. Within four days, most acorns were eaten — primarily by wood mice at night and Eurasian jays during the day. Smaller acorns disappeared faster than larger ones, and while burying acorns slowed things down slightly, it didn't reliably prevent loss overall.
Key Findings
Most acorn removal occurred within 4 days of sowing, with holm oak (smallest acorns) lost at significantly higher rates than English oak (largest acorns, p=0.010).
Wood mice foraged exclusively at night in forest understory, while Eurasian jays operated strictly during the day across both open and shaded areas — creating a round-the-clock predation window.
Burying acorns changed predator behavior (more digging and exploration) but did not consistently reduce total losses compared to surface placement at the plot level.
chevron_right Technical Summary
Even when deer are fenced out, oak woodland restoration fails because mice and jays eat most acorns within days. Burying acorns and choosing the right microhabitat helps, but no single technique reliably stops early seed loss.
Abstract Preview
Regeneration in Mediterranean oak woodlands is increasingly constrained by intense post-dispersal seed predation. Inside an ungulate-exclosure fence in the Castelporziano Presidential Estate (Centr...
open_in_new Read full abstractAbstract copyright held by the original publisher.
Species Mentioned
Was this useful?
Urban Tree Canopy Reduces Heat-Related Mortality by 39% in European Cities
Trees in your local park or street aren't just pretty — they are literally keeping people alive during heatwaves, and planting even a modest number of the ri...
Quercus pubescens, commonly known as the downy oak, pubescent oak or Italian oak, is a species of white oak native to southern Europe and southwest Asia. It is found from northern Spain (Pyrenees) and France in the West to Turkey and the Caucasus in the East.