David and Goliath: comparative use of facilitation and competition studies in the plant ecology literature

Competition and facilitation are extensively studied in plant ecology and are central to ecological theory. However, these processes do not occur in isolation from each other and should be studied concurrently and synthetically. Here, we compare the relative citation success of studies that focus on either side of the same interaction coin in terms of number of publications and citations per publication in six of the following major themes in plant ecology: biogeography, populations, communities, ecosystems, evolution and conservation. There were eight times more publications on plant competition than on facilitation but this is not surprising given its long history of comprehensive and relatively exclusive study in plant ecology. Although studies of facilitation comprised a smaller body of literature, the mean citation rate for each publication was equivalent to that of competition studies. Thus, facilitation studies are being used as much as competition. These patterns of use by the ecological community clearly indicate that both aspects of plant interactions address broad themes and that studies on plant interactions should now strive to either test both simultaneously or at the very minimum include interpretations and relevant literature from both sets of ideas. Importantly, these broad trends illustrate the old axiom that quality and not quantity of studies may be a consideration in the success of a sub-discipline.