Tree species that recover quickly from frost damage may have an advantage going forward. Wild cherries and oaks, for example, have good strategies for surviving frost.
Trees sprout earlier because of climate change. According to a new study by the Swiss Federal Institute for Forestry, Snow and Landscape Research (WSL), this has far-reaching consequences. Because the risk of late frost remains high. Tree species that recover quickly from frost damage may therefore have an advantage going forward, as the WSL wrote in a statement on Tuesday.
The study published in the journal Functional Ecology shows that trees that recover well from frost can sprout earlier in the year, despite the risk of frost. According to the study, this capacity is becoming increasingly important with climate change. While it often warms early in the year, the risk of late frosts should remain at least as high during this time. In this way, frost-tolerant species can prevail over frost-sensitive species in the future. That would change Switzerland’s forests in the long run.
Hornbeam and beech trees severely affected
Finding the right time for leaf sprouting is a risky task for deciduous trees. Too soon and the entire investment can fall prey to a single frost; too late and scarce resources such as water, nutrients and light can already be consumed by competing neighboring plants.
How much risk a tree must take depends on its ability to recover from frost. During the course of evolution, an ideal time for leaf sprouting was established for each species.
For the study, the researchers allowed potted trees to sprout in a heating chamber and then exposed them to frost in a cooling chamber. According to the study, wild cherry trees and oaks have good strategies for surviving frost. Wild cherries form a new bud from the bottom, and oaks have many spare buds. In contrast, one out of three hornbeams examined did not survive the frost. Red beeches were also more affected, formed smaller leaves and had sparse crowns.