The Significance of Growth-Rate Comparisons for Plant Ecology

It is now apparent that slow growth rates are characteristic of plants from at least three types of unfavorable habitat. In discussing such growth rates as adaptations to the environment, it is necessary to bear in mind the great diversity of other adaptations to low levels of environmental resources. For example, in interspecific comparisons, different transpiration-control mechanisms may greatly complicate the relationship between growth rate and drought susceptibility. Nevertheless, it seems clear that the environmental selection of plants with slow growth rates is a frequent and simple form of adaptation to limiting levels of environmental factors. Certainly growth-rate comparisons are often a valuable way of beginning to investigate why plants grow where they do.