Elias Landolt (1926–2013) was a Swiss geobotanist,[1] known for his publications on Switzerland's native flora[2] and Lemnoideae (popularly called duckweeds or water lenses).

At ETH Zurich (ETHZ), Elias Landolt (the younger) studied natural science from 1945 to 1949 and received his doctorate there in 1953 under the professors Ernst Gäumann and Walo Koch with a dissertation on Ranunculus montanus (mountain buttercup).

In 1957 he completed his habilitation thesis Physiologische und ökologische Untersuchungen an Lemnaceen (Physiological and ecological studies on duckweeds).

Landolt became known in Switzerland mainly for his research and publications on the Swiss and Alpine flora, and later also for his extensive mapping for the city of Zürich and the Sihlwald to the south.

[citation needed] Landolt's 1977 publication of ecological Indicator values and biological attributes of the flora of Switzerland and the Alps made him internationally known.