In the autumn of 1925, Mao **, who had passed the year of his establishment, wrote this popular poem: "The dung was the marquis of ten thousand households back then. ”

It shows the arrogance of this peasant boy who looks down on the powerful and insists on the belief that "rebellion is justified" all his life. From the point of view of economic history, the equating of the ten thousand households with dung still greatly exalts them.

In the Ming Dynasty, the fields in the south of the Yangtze River accounted for only more than 6% of the country, but the tax grain accounted for more than 1/5 of the country. It is precisely because of the development of manure processing technology that the agricultural development in Jiangnan is unique in the world. If there were no dung in the south of the Yangtze River, there would be no grain that was continuously transported to Beijing and other places, and there would be no powerful people with fat brains. These wine bags, rice bags, and walking corpses of the ten thousand households, where can they compare to the dung that supports the foundation of the Empire State Building!

In ancient times, there was no such thing as chemical fertilizer, and after three or five years of land cultivation, the fertility decreased, and the crop harvest would decline, and many people understood this path. Therefore, working people can often only adopt simple methods such as fallow and rotation to slowly restore the fertility of the land, or plant two crops in three years, or plant one season of wheat and millet and one season of beans.

In the long-term cultivation, farmers found that cultivation relies on human manure, river pond silt, leaching plant stems and leaves, plant ash, leachable garbage, village ditch sewage and peanut and bean bran as fertilizers can increase the yield per mu, and after the end of the Ming Dynasty and the beginning of the Qing Dynasty, the composting technology has made great progress.

At the end of the Song Dynasty, the agricultural book "Planting Art Must Be Used" said: "If the land is cultivated for a long time, it will be consumed".

Chen Yang's "Book of Agriculture" said: "If the soil is not long, the grass and trees will not grow, and if the qi is weak, the creatures will not fail." Wherever the fields have been planted for three or five years, their strength has been exhausted."

The use of fallow to restore the fertility of the land is too simple and backward, and it also greatly affects the harvest. Therefore, the people have long discovered fertilization to maintain the fertility of the land, and some people have already concluded that the manure of people and animals and the ash of the stove are useless, and as soon as they enter the field, they will be turned into cloth and silk.

It's just that the Tang people's use of human and animal dung is too simple, and generally only the simplest dung. Although this kind of manure can also be fertile, the conversion rate is still too low.

For example, if it is the same pile of pig manure, if it is managed legally, the effect will be great, and if it is not legal, the effect will be small, or even none.

Manure cannot be applied directly, otherwise it will sometimes hurt crops and is easy to burn seedlings. The Tang people's manure compost is also to let the manure rot and prevent the seedlings from burning the roots.

With the changes of the times, manure has also undergone different development processes: "steamed manure method", "simmering manure method", "cellar manure method" to "boiling manure method".

The processing technology of manure is not complicated, and it is mainly divided into northern and southern manure.

The production process of manure in the north is as follows: cut the corn stalks into small sections in autumn, and then pile them into a pile in the form of warp and weft in the order of up and down, pour manure and urine water on it, and it must achieve the effect of soaking it for a long time, and then let it ferment, and you can also add the plant ash or charcoal rich in potassium fertilizer after burning, and it will be dried into small pieces of gray-black fertilizer or gray-black fertilizer water with water quality in the spring of the next year, which is manure; Wheat straw stacks can also be used to make manure. In the process of manure making, the stems, vines, and leaves of other plants or the branches of dead trees picked up by cleaning the yard are always added to the straw stack.

The production process of manure in the south is: Yicheng and various polder towns, in the old days, farmers in the suburbs carried buckets into the city at night to collect manure from each household, commonly known as "urine pouring". The manure was transported by bicycle hanging buckets, and the way of carrying manure was gradually replaced, mainly by the improvement of transportation tools.

In addition, there is a kind of pig poop picking.

Compared with the modern use of chemical fertilizers, manure has little adverse effect on crops, so manure must be used for cultivating fields since ancient times, including human manure, chicken manure, pig manure, cow manure and so on.

Zhen Qian also knows a method, which is to dig a large pond, throw all kinds of animal manure into a huge manure pit along with some straw and vegetable roots, add urine, water, etc., and then cover it for fermentation, which is similar to biogas digester fermentation, although the fermentation is slow, but the consumption of organic matter is less, and the slag fertilizer and biogas slurry have high fertility, especially the biogas slurry can even be used as an insecticide.

This method is an excellent manure processing method, which can make the manure conversion efficiency higher, and the yield per mu can be doubled.

Later generations may be disgusted when they talk about dung, but in the past, it was a rare treasure in the hearts of farmers.

Sir Stanton, a member of the famous Magalny Mission, wrote in his account of his visit to China: "The Chinese pay great attention to the accumulation of fat. A large number of old people, women and children, who could not afford to do other work, carried a basket behind their backs and a wooden rake in their hands, and went out into the streets, on the highways, and on both sides of the riverbank, looking for garbage that could be used as fertilizer. …… In the Chinese peasant family, any old, weak and crippled person is useful, they cannot do other labor, but they can accumulate manure and make fertilizer"; "In addition to poultry manure, the Chinese attach the most importance to human urine and manure.... The Chinese rake this manure and accumulate it, mix it into hard loam to make blocks, and dry it in the sun. This manure can be sold as a commodity to farmers"; At the same time, farmers "place large vats in their fields or on the side of highways and bury them in the ground for pedestrians to defecate." A latrine is sometimes built near a village or next to a road, with a manure tank in it. Put some straw on the upper layer at any time in the tank to stop evaporation and consumption" (see "The British Envoy's Meeting with Qianlong").

It is recorded that the collection of manure began in the Southern Song Dynasty, and before that, there were special people in the city to collect manure, but it was all in order to clean the urban environment, and it had nothing to do with the use of manure.

Therefore, Xu Guangqi said: "The field is more fertile, and the dung is more." The same is true of densely populated areas in villages" (see The Complete Book of Agricultural Administration).

During the Southern Song Dynasty, Hangzhou already had special personnel to collect and transport urban human feces. Wu Zimu said that Hangzhou "has a busy household registration, and the homes of small people in the streets and alleys have no pit toilets, only use toilets, and there are people who come out of dung every day, which is called 'tilting their feet'." Each has its own customers, and they dare not encroach. or if there is a trespass, the dung owner will fight with it, or even after a great lawsuit by the government, he will win and then himself."

Zhen Qianke did not go to the county town to collect manure, but raised a large number of livestock in Sendai Village, and collected the manure of pigs, sheep, chickens and ducks as raw materials for manure, and raised pigs, sheep, chickens and ducks were sold in the county town, and the money earned was then purchased for grain, creating a virtuous circle.

Due to the use of a large amount of manure, the yield per mu of Sendai Village reached more than four stones, and not only Zhen Qian benefited from it, but also the surrounding farmers also followed suit, so that Zhen Qian had more say in Sendai Village.

There is a risk and price to do anything, and the yield of more than four stones per mu is only a multiple-fold increase in land grain for ordinary peasants, but for officials, the meaning is completely different. The feudal society was based on agriculture, and the yield per mu was directly linked to the black yarn hats of the officials, and it is not difficult to imagine the madness of the Tang Dynasty officials after learning the news.

Zhen Qian doesn't want to be targeted by the imperial court now, and secretly strengthening his strength is the foundation of survival.

Zhen Qian didn't want to report to the imperial court, and the officials wouldn't go down to the countryside to inspect the farming situation, so naturally they wouldn't find this good opportunity to get promoted and make a fortune!

Officials don't know, but that doesn't mean no one knows about it, and farmers in Sendai village drooled when they saw the heavy ears of wheat in the autumn harvest fields. However, Zhen Qian did not cherish himself, provided manure to the surrounding farmers free of charge, and also paid for pigs, sheep, chickens and ducks to be raised by the farmers, so that the interests of the surrounding farmers and Zhen Qian were firmly tied together.

The peasants of this era were simple and simple, and whoever was good to them would support him without hesitation, and naturally they would not tell the government this secret.