45 



The next fifteen hundred years accepted the obsers ations and theories 

 of the Romans, which may be found collected in Pliny. For E. Meyer^ 

 reports from Petrus de Crescentiis who wrote his great work in 1305, 

 the first eight books of which treat of agriculture, that since Palladius 

 no one had written anything in Latin on agriculture. Only fragments of 

 the Greek collection of the Geoponika were to be found. The older works 

 of Varro and Columella we'-e no longer suited to existing conditions, so that 

 there was need of an up-to-date book on agriculture. Yet the book by Petrus 

 de Crescentiis actually contained less than the books of the older authors, al- 

 though he strived for a scientific foundation for agriculture and gave num- 

 erous directions for grafting various kinds of trees, in accordance with the 

 favorite pursuits of antiquity and of the middle ages. Tn the same way in 

 1600 Colerus- also only repeated the earlier statements regarding the 

 outpushings of the bark. — "Inflammation of trees" ("Schwulst der Bewne") 

 under which there develops a putrid liciuid. In this book the influence of the 

 stars was believed in, with unshaken firmness. For example, in his "Horti- 

 cultura" published in 1631, the renovvmed Professor Peter Tauremberg-^ of 

 Rostock relates that certain stars like Orion, the Pleiades and others exert 

 an especially injurious influence and that, as a result of injurious atmos- 

 pheric influences, the so-called "secret evils" arise, among which belong rust, 

 carbuncle and mildew. 



We can naturally expect to find progress in the recognition of the sig- 

 nificance of disease among practical workers, whose cultural efl^orts are most 

 sensitively disturbed by injuries making themselves felt in their work. The 

 book of the "Electoral Superintendent of Gardens," — Heinrich Hesze"', — 

 which was famous in its time, is interesting in this connection. He 

 speaks of the blasting of the branches which he calls "blight and cold," 

 "otherwise there are three chief causes for the blighting of trees. First, 

 superfluous moisture which, with inflammation of the sap, is collected be- 

 tween wood and bark, distending the latter and blighting and blasting it. The 

 second is this, — that of times, thoughtlessly and with a lack of judgment, the 

 tree is set in a postion dififerent from the one in which it stood before. This is 

 very injurious, since the bark where it is brownish and has been exposed to 

 the east or south, is therefore much harder than on the sides toward the 

 north or west. These are generally green, tender and immature. There-fore, 

 some injury must inevitably arise from this, since the north side is not at 

 all accustomed to the southern sun and is not only blasted by the great heat 

 but in the spring is injured by the hard frosts ; the bark is raised, then later 

 in the day dried up and scorched by the sun. From this the bUght at once 

 arises, since it is commonly noticed on the southern side." Flere we have posi- 

 tive personal observations. The author relates further that he has never- 



1 Geschichte der Botanik. Vol. IV, p. 148. 



^ M. .loannis Coleri, Oeconomia und Haussbuch etc. Ander Theil. Wittenberg- 

 1600. Book V. Chapter 12. 



3 Petri Laurembergii, Rostochiensis Horticultura. Francofurti 1631. Cap. XXXV. 



4 Heinrich Heszens, Neue Gartenlust etc., enlarged and provided with three 

 useful indices by Theodorum Phytologum. 1690. Chapter VIII. 



