Some plants mainly use day length as an indicator of the season.

一些植物主要使用日长作为季节的指标。

Wigge explains: 'Oak trees rely much more on temperature, likely using phytochromes as thermometers to dictate development, whereas ash trees rely on measuring day length to determine their seasonal timing.

Wigge 解释说：“橡树更依赖于温度，可能使用光敏色素作为温度计来指示发育，而白蜡树则依靠测量日长来确定它们的季节时间。