PubMed · 2026-06-08
European beech trees in the Netherlands have stopped their boom-and-bust seed cycles since the late 2000s, now producing low but steady crops every year. This 'masting breakdown' means seeds are more likely to be eaten by predators and less likely to be pollinated, threatening the trees' long-term reproduction — and warming temperatures are only part of the explanation.
Synchrony and year-to-year variation in beechnut production declined significantly, with a masting breakdown occurring in the late 2000s after which seed output became consistently low rather than episodic.
Predation risk on seeds increased nearly three-fold following the masting breakdown, while pollination efficiency also declined — together substantially reducing the reproductive fitness benefits that masting normally provides.
Temperature changes (but not precipitation changes) over time partially explained the shift in masting patterns, yet climate alone cannot account for the full breakdown, implicating additional unidentified interacting factors.
