The fourth solar term of spring, the "Vernal Equinox," is coming, which, as the name suggests, divides spring in two. In the lunar calendar, the time between spring and summer is usually called spring, and the spring equinox is exactly in the center, and the ancient books "Seventy-two Waiting Solutions of the Moon Order", "Spring and Autumn Dew", and the Lunar Book all have the same explanation for it: "The spring equinox, yin and yang are half, so the day and night are equal and cold and hot." Therefore, the ancients often called it "day and night", "day and night", "mid-spring moon" and so on. At the same time, the arrival of the spring equinox also marks the arrival of the equinox of day and night, and the balance of cold and summer. The spring equinox means a mild climate, abundant rain and bright sunshine, and it is no wonder that Shao Yong once said that "the four hours only love spring, and spring loves the spring equinox even more." However, the twenty-four solar terms are a different scene in the folk, the ancient people relied on the sky to eat, and the impact of the spring equinox on agricultural affairs was not so pleasant. There is a saying that "the spring equinox does not rain, and graves are raised everywhere" can be glimpsed from it, and the colloquialism is inevitably exaggerated, but there is some truth in it.
There is a saying in the poem that "good rain knows the season, when spring is happening", in fact, spring rain is not always so "good". In addition to the sayings in the title, there are many sayings that reflect the scarcity of spring rain, such as the phrase "The spring equinox wheat rises, and the rain is as expensive as gold." Scarce things are precious, and rain is no exception, which shows the mood of the ancients looking forward to Ganlin before and after the spring equinox. Especially in the Shaanxi area, the temperature rose rapidly to about 10 °C around the time of the spring equinox, and after the winter wheat returned to green, it entered the stage of active growth. The so-called jointing, also known as the gestational ear stage, is the late stage of wheat ear differentiation, and the folk call this period of wheat "fetal wealth", which is the key period to determine the winter wheat harvest.
If it does not rain at this time, not only is the water insufficient, the fertilizer is difficult to fully absorb, and the nutrients of the wheat will be "congenitally insufficient", which will seriously affect the differentiation of the spikelets, and there will be a situation where the ears are small and the ears are small, which means that the yield is reduced and the harvest is poor, which the people call "poor hunger in the fetus". On the contrary, if there is sufficient rain before and after the spring equinox, the absorption of wheat nutrients can be guaranteed, so that the differentiation of small ears is more and larger, and the folk call such wheat ears "wheat mountains", which means that the harvest foundation of winter wheat has been laid. For the ancients who made a living from farming, there were also harsh taxes and miscellaneous taxes in the case of poor harvests, which was undoubtedly a disaster. In ancient times, when people's livelihoods were difficult, food shortages often meant more deaths, and it is no wonder that the saying goes, "graves are everywhere".
In addition to winter wheat, beans are sown and seedlings are also planted during the spring equinox in southern Shaanxi. Because of the rise in temperature, the climate on both sides of the Han River has become warmer, and the local area mostly sows pulse crops on slopes and field edges to meet the requirements of seed germination on the soil. At this time, the most indispensable thing is water, the germination stage of the seed has more than 100% water absorption rate, water is almost double the weight of the seed, so the local people usually sow beans in time after the spring rains. With the end of the sowing of beans, the temperature rose to 20 ° C again, which is just in line with the minimum temperature requirements of the mother field, and the people who have just sown the beans have to start sowing rice seedlings non-stop, so there is a local saying that "the spring equinox has rain and the family is busy, first plant beans and then raise seedlings".
In general, the water irrigation conditions of agriculture in many areas in ancient times were very backward, because of the terrain and geographical reasons, people made people pay for irrigation. Therefore, in ancient times, in addition to wars, countless people starved to death every year because of poor harvest and lack of food. Behind the "eating from the sky" is the tragic reality of "the heavens and the earth are not benevolent and all things are dogs", and the situation of "raising graves everywhere" in barren and remote areas because of the lack of rain and poor harvest is also ancient. However, these sayings have obvious regionality, such as the area south of the Yangtze River, around the spring equinox precipitation increased sharply, often flood disasters, the ancients called it "peach blossom flood", the so-called "drought of drought and death of waterlogging" is more or less so. Living in today's rapid development of science and technology, in the face of natural disasters with more scientific protection, we are really the happiest generation in history so far.