How does the elm meteorological tree predict the weather?

There is a strange elm tree next to Dateng Village, Gaoguan Township, Hexian County, Anhui Province. This tree is almost 7 meters high, with a short and thick trunk and a circumference of more than 3 meters. Its crown is like a big umbrella, covering an area of 100 square meters. Locals call it Pu Shu, who is over 400 years old.

Surprisingly, this is a "meteorological tree" that can predict the drought and flood in that year. People can infer the rainfall of that year according to the time when trees germinate and the density of leaves. If this tree sprouts in front of Grain Rain and grows luxuriantly, it indicates that there will be more rain, high water level and frequent floods. If, like other Pu Shu, it germinates according to the season and leaves grow sparsely and densely, then it is a good year with good weather; If the germination is delayed and the leaves grow less, it means that there was less rain and serious drought in that year. Decades of observation data prove that it is quite accurate to predict the drought and flood in that year.

Why is this? After a preliminary investigation, scientists believe that this may be because this tree should be particularly sensitive to the ecological environment, which has played such a strange role.

There is also a meteorological tree next to Dinglongshan Village in Xincheng County, Guangxi, which can predict the weather in sunny and rainy days. This tree is very tall, 20 meters high and about 0.7 meters in diameter. Locals call it the green bar tree. Interestingly, the color of its leaves changes with the weather. Sunny days, usually dark green; When the leaves turn red, it indicates that there will be heavy rain in this area in a day or two; After the rain stopped, the leaves turned dark green again. Over the years, local farmers have predicted sunny and rainy days according to the color of leaves and arranged farm work.