A new study found that trees as well as other plants sleep during warmer winters as their way to adapt to climate change.
Normally, plants follow a developmental pattern in sync with the shifting seasons. However, with the emergence of global warming, changes in climate has been ubiquitous.
A team of scientists gathered data and analyzed 36 shrub and tree species to investigate the extent of effects of warmer winters to plants.
Thirty-centimeter twigs were put into climate-controlled enclosures under various light conditions and temperatures. The six-week experiment gave the researchers ample time to check the adaptation techniques of each plant species to cold and warm weather.
"Contrary to previous assumptions, the increasing length of the day in spring plays no big role in the timing of budding. An ample 'cold sleep' is what plants need in order to wake up on time in the spring," said lead researcher Julia Laube in a press release.
Trees like the beech and oak sleep during winter seasons to survive the freezing cold during frosts in the late spring. Bush species on the other hand like hazel shrubs budburst in the early spring.
Their findings revealed that the impact of the cold temperatures is critical to the ecosystems in the woods. Mild winters tend to give trees to delay development of the leaves. In turn, it allows sunshine to fall upon the ground come springtime, which gives the bushes and other vegetation the benefits of the sun's rays. As a result, the shrubs bloom at an earlier schedule which may impact growing trees not yet tall enough to withstand their invasion.
According to researcher Annette Menzel,"Overall, however, a chaotic picture emerges. Through warmer winters, the usual sequence of leaf development can get completely mixed up. Many of the cultivated species that are at home today in central Europe come originally from warmer climate zones. In the absence of adequate protection against freezing, they could become victims of their own too-flexible adaptation-and freeze to death in a late frost in the spring."
The most hugely affected by the cold temperatures were the hornbeam, beech and sugar maple species. Their budburst were considerably delayed because of condensed periods of winter.
The study was published in the Oct. 30 issue of the Global Change Biology.
