Henry Allan Gleason (1882–1975)


1793 Alexander von Humboldt uses the word “association” to sum up the range of plant types in a particular habitat.

1899 In the US, Henry Cowles states that vegetation develops in stages, in a process he calls plant succession.

1916 Frederic Clements posits the idea of a climax community as a single organism.


1935 Arthur Tansley coins the term “ecosystem.”

1947 Robert H. Whittaker begins field studies that will refute Clements’s holistic idea of plant communities.

1959 John Curtis boosts Henry Gleason’s reputation with numerical studies of prairie plant communities.

When American ...

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