Why didn't the Qin Dynasty burn books on medicine, divination and planting trees?

I think the main reason is that these books have little to do with politics, have no reactionary ideas and are harmless to the dynasty.

The incident of burning books and burying Confucianism was Qin Shihuang's cruel suppression of dissidents in the ideological field. In the thirty-fourth year of the first emperor (2 13 BC), Qin Shihuang gave a banquet in Xianyang Palace, and the first emperor was very happy. But there is a conservative doctor named Chun Yuyue, whose native place is Qi. He criticized Zhou's flattery on the spot. He said: "Yin Zhou Wang is over 1,000 years old and has contributed to his children and helped himself." He criticized Qin Shihuang for abolishing the enfeoffment system and setting up counties. Said that if the minister usurped power, there was no way to save himself. He also sarcastically said: "Those who can live for a long time without learning from the past are not heard." Li Si, the prime minister, retorted on the spot. He accused Chun of being a "foolish Confucian", and also accused Confucian scholars of "learning from the past but not learning from the present, confusing the leaders of Guizhou" and "being insincere and unable to get out of the way, praising the Lord's name, taking different things as high and attracting group slander". He thought that such a group of Confucian scholars was a dangerous force, suggested that the first emperor resolutely stop their illegal activities, and put forward the suggestion of burning books to bury Confucianism. Main contents: (1) All the history books of the six countries were burned except Ji Qin;

(2) Except for doctors' collection, all poems, books and books in hundreds of languages are collected in the county and burned under the supervision of the county magistrate and commandant;

(3) Those who talk about "poetry" and "books" abandon the city, take the ancient as their home, and those who don't mention it are guilty of the same crime, so that they will not burn for the next 30 days and be regarded as the city;

(4) Books such as medicine, divination and tree planting are not prohibited;

(5) After learning laws and regulations, we should take officials as teachers.

Qin Shihuang approved this proposal, so book burning happened all over the country.

(quote)