 Afterwards, he worked at the Botanical Museum in Berlin and at the botanic garden in Victoria, Kamerun.In 1921 he became an associate professor of phytogeography at the University of Breslau, where in 1927 he attained a full professorship.In 1908 he conducted botanical studies in the Malay Peninsula and the Dutch East Indies, where he also collected rattan plants and seed for importation to German colonies.