Karl Gustav Sanio and the First Scientific Description of Compression Wood

Compression wood was first described in 1860 by the briIIiant German bot an ist Karl Gustav Sanio, a fact that seems to have remained unnoticed until now. Following abrief review of Sanio's life and major achievements, his research on compression wood is discussed with reference to his two articles from 1860 and 1873. Sanio studied the distribution of compression wood in the stern, root, and branches of Picea abies and Pinus sylvestris. He was the first to note that it is formed in roots only after exposure, and that compression wood in a branch often continues into the stern. The tracheids in compression wood according to Sanio had a rounded outline and narrow lumen and were separated from one another by intercellular spaces. A thin, heavily lignified primary wall was followed by a thick secondary wall, composed of an outer layer that was thickened at the cell corners (S]), an intermediate, highly lignified layer (outer S2), and an inner layer with spiral striations (inner S2). Lignification was initiated in the primary wall at the cell corners before the secondary wall had been completed. All these results have since been confirmed by other investigators, some of them only recently.