Global warming is generally expected to bring spring forward but a connected influx of plant species from warmer southern latitudes could counteract this effect, said a study. Ludwig Maximilian University of Munich (LMU) biologist Susanne Renner and her research group have now looked at the effects of this warming trend on the timing of leaf emergence (leaf-out) in a broad range of shrubs and trees. “It is widely believed that warmer temperatures will extend the growing season and that leaf-out in our flora will occur at progressively earlier times in the year,” said Renner. “However, whether air temperature or day-length is the dominant factor determining the date of leaf-out is actually known for very few of the thousands of species of trees and shrubs,” he added. Temperature and day-length are the primary triggers for leaf development, and selective forces during the course of evolution have determined which signal is actually used in a given species.

Click Here To Read More