Bai Juyi's "Peach Blossom in Dalin Temple" shows a truth about phenology contained in this poem.

Bai Juyi's "Peach Blossom in Mountain Temple begins to bloom in April" ("Peach Blossom in Dalin Temple") shows the difference between the mountain climate and the plain climate.

The vertical climate in mountain and the poem of Bai Juyi in Tang Dynasty: "Peach Blossom in Mountain Temple begins to bloom in April. I hate spring for a long time, but I don't know where to turn". It vividly reflects that the temperature increases with the altitude. The vertical difference of phenology in mountainous areas. Usually, the temperature drops by .6℃ every 1 meters above sea level. The altitude of Dalin Temple in Lushan Mountain is between 1,1 and 1,2 meters, which is about 6℃ lower than that of "human" (the flat land in Jiujiang City, with an average elevation of 32 meters). Therefore, the flowering time of peach blossoms is 2 to 3 days behind, so the phenology on the mountain is delayed by one month compared with that on the mountain.