Beech tree crowns full of seeds
Last summer’s heat and drought had an impact on the health of various tree species. The early leaf drop in beech was reported in the press on several occasions.
In addition, seed production in beech trees was also notable. In the forest vitality monitoring network (ICP Forests – Level I), 52% of the beech trees were found to exhibit moderate to heavy seed production. Years with such above-average seed production are called “mast years.” Beech trees that produce a lot of seed tend to have sparser foliage. Consequently, many beech trees appeared stunted, particularly due to the combination of seed production and early leaf drop caused by drought stress.
In the second half of April, we observed massive flowering of the beech trees in the monitoring network for intensive forest ecosystem monitoring (ICP Forests – Level II), combined with ideal weather conditions for pollination. Seed production was also good in these plot areas. In the Level II plot, a portion of the seeds is collected for biomass determination and chemical analysis. The most recent results are not yet available, but it is clear that the plots in the Wijnendalebos and the Sonian Forest achieve very high figures for seed production.
Climate change affects both the timing of leaf emergence in the spring and leaf fall in the fall. Flowering and seed formation are also influenced by weather conditions. A recent publication shows that continued seed production is guaranteed following successful flowering and pollination in the spring, regardless of drought conditions in the summer or fall. However, drought can have a negative effect on seed germination and seedling survival, which limits the chances of successful natural regeneration.
Geert Sioen, Arne Verstraeten