First of all, the jujube trees here are not specifically jujube trees, but "mulberry dates", which generally refer to farmers' sideline business after the Han Dynasty. As far as "mulberry jujube" is concerned, when Du Shu discussed the importance of the Three Kingdoms and Yizhou, he once mentioned that "the number of registered permanent residence is the most, and the fields are cultivated, and the mulberry jujube is spared." Shu Wei also mentioned: "What the army does must not hurt the people." There is a saying in the Book of the New Tang Dynasty: "Because of the teacher's mistake, I dare not cut mulberry dates." The usage of these "mulberry dates" not only refers to mulberry trees and jujube trees, but also refers to farmers' sideline activities other than growing grain in farmland. The main sideline crops in ancient China were mulberry, elm and jujube. The order of the Northern Qi Dynasty said, "Every Ding Ci has a field of 20 mu, which is a mulberry field, including 50 mulberry trees and 3 elms, and dates have no roots." In the Sui Dynasty, the trees in Yongyetian were mulberry, elm and jujube. In the Tang Dynasty, there were still "indoor perpetual fields, more than 50 mulberry trees and more than 10 elm jujube trees." Why do you want to do sideline business? The answer is that simple farming is not enough, but also needs "the capital to prepare for life and the tools to support life." As mentioned in middle school history textbooks, China's ancient agriculture was characterized by a self-sufficient small-scale peasant economy. Self-sufficiency here is not just about eating yourself. To wear clothes, you have to plant mulberry books, make furniture, and plant elms. This is called "keeping in good health". According to Records of the Ming Dynasty, when Zhu Yuanzhang ordered the planting of mulberry dates, he said: "Human nature is complacent, and hunger is forgotten and warm." Once a pawn encounters a fierce famine, he is at a loss. I know the people are in trouble, and I try my best to persuade them to be salty and warm. Since the age of 20, the people have been rich and the fields have been stable. If you can worry about it, you can't forget the preventive measures in one day. The Ministry of Industry has instructed the people, but if there is space, you can plant the date. Or if you are sorry, you can help get dressed. "Zhu Yuanzhang said that things change. Maybe one day when God is not present, the grain harvest will be poor and there will be nothing to eat. You can still eat dates at this time! This is "preparing for life. "

Although people eat jujube as fruit now, it was really an important food in the past. As early as the Warring States period, it was recorded in Han Feizi that there was a famine in the State of Qin, saying that "the grass in the five gardens: vegetables, acorns, dates and chestnuts are enough for the people, so please send them". When Su Qin went to lobby the state of Yan, he mentioned that "there are dates and chestnuts in the north, although the people can't cultivate them."

One more thing is worth mentioning. Xin Qiji said: "Northerners don't want other people's health care, so they live in poor families. The south is mostly sick farmers, but it is prosperous, and the rich and the poor are not embarrassed. " Everyone has planted trees, so there is no need to go out to buy and sell. It is also conducive to narrowing the gap between the rich and the poor and social stability. Do you think the emperor is happy? In addition, we have a tradition of eating dates since ancient times. Let's read The Book of Songs, which reflects the simple life of working people in China. Among them, the wind is in July: the fire is full in July and clothes are given in September. The first day I was fat, the next day I was fierce. No clothes, no brown, why did you die? On the third and fourth day, I stood on tiptoe. With my daughter-in-law, we are very happy to see each other in the south. Fire is full in July, and clothes are delivered in September. In spring, the sun shines and Amin is in the sky. The woman took the basket and followed it. Love looks for soft mulberry, and spring comes late. Take Qi Qi for example, this woman is sad in her heart, almost like her son. Fire is full in July and reeds are full in August. Silkworm, moon, mulberry, take axe fork, cut far and wide, as the mother mulberry. Singing in July, achievement in August. Xuan zai Huang, I, for the childe petticoats. Beautiful in April, singing in May. Harvest in August and crush in October. A day to raccoon, fox, for the child. The next day, they were still the same, carrying martial arts. Talk in private, offer in public. In May, I moved stocks, and in June, I raised feathers. Wild July, in August. I was at home in September, and crickets came under my bed in October. The dome suffocated the mouse, stuffed it in, licked my wife and son, and said that I would enter this room in another era. In June, food is depressing and stinging, and in July, hunger is speechless. Peel dates in August and get rice in October. To this end, spring wine is used to celebrate longevity, eating melons in July and breaking pots in August. In September, Uncle Zhu paid for tea picking and ate my peasant woman. Build a yard in September and harvest crops in October. The millet is heavy, and the grass is shelled. Well, I am a farmer. Because I have the same crops, I went to work in the palace. The day is in the grass and the night is in the rope. I was so anxious to hitch a ride in the house that I began to broadcast Baigu. The next day, I cut the ice and rushed, and on the third day, Lingyin was satisfied. On the fourth day, its flea sacrificed the lamb to the leek. First frost in September, washing the floor in October. A friend who drinks wine kills a sheep every day. When you go to court, you are called a man and live forever.