In 1777, an economics faculty was created at the University of Giessen with new subjects such as veterinary medicine and agricultural science. This also included forestry, which first appeared in the course catalog in the summer semester of 1778. One of the first students was Georg Ludwig Hartig, who later formulated the concept of sustainability. The economics faculty failed after only eight years, but forestry was retained with its own institute in the philosophy faculty. This academic upgrade of forestry was unique up to that point; the institute was the first forestry teaching institute in the world at a university.
In order to accommodate the new subject, a forest botany section was added to the Giessen Botanical Garden in 1800. From 1825 onwards it was relocated to the Schiffenberg Forest. The reason for this was that the Hessian Forestry Institute had been founded in the same year, which was initially an independent state institution and was not incorporated into the university until 1831. Johann Christian Hundeshagen (1783–1834), who had previously headed the forestry school, was also appointed director of the institute.
Until then, the Giessen forest had been severely damaged by excessive logging and forest grazing. Pigs, sheep and goats were driven into the forest and gnawed at the young plants that could not grow back. The fallen leaves were collected and scattered in the stables (forest litter), so that nutrients were constantly being removed from the soil. Although forest regulations restricted use in many ways, from a forestry science perspective they proceeded haphazardly.
From 1824 to 1829, district forester Carl Justus Heyer had almost 400 hectares of wasteland reforested against the bitter resistance of Giessen's cattle owners. In order to break their resistance, he sometimes had them work at night and planted the trees from the most distant points towards the city. Because of their undemanding nature, he planted mainly pine trees and later mixed in beech and oak (even today, large old pine stands in the Schiffenberger Forest can be traced back to Heyer).