Equilibrium marshes

Yesterday I was reading Courtney Brown's Remote Viewing: The Science and Theory of Nonphysical Perception. Like J. W. Dunne before him, Brown accepts the very strong evidence for the reality of precognition and retrocognition (the direct perception of future and past states of affairs) and attempts a theoretical explanation. While Dunne adds additional dimensions of time, Brown takes the opposite tack of suppressing time altogether. He demonstrates how this might be done with the following phase diagram of two interacting populations, which was created by dividing one equation by another so as to eliminate time as a variable:

I'd seen phase diagrams before but had never seen equilibria referred to as "marshes." A Google search seems to confirm that this terminology is virtually unique to Brown, since all I can find are diagrams dealing with the ecology of actual wetlands, publications by people named Marsh, and other books by Courtney Brown. Here's how the term is defined in Brown's Differential Equations: A Modeling Approach:

Especially with social science topics in which change is slow, differential equation systems often do not have a chance to evolve to the point where the system trajectories actually arrive at an equilibrium. In reality, the trajectories "bog down" when they pass anywhere near the equilibrium in what is called an "equilibrium marsh." Placing the equilibrium marshes in the phase diagram is a useful way to identify those areas where trajectory velocity is so slow that the system essentially comes to a near halt even though equilibrium has not been achieved (p. 56).

A similar explanation is given in Serpents in the Sand: Essays in the Nonlinear Nature of Politics and Human Destiny, in the essay "Anatomy of a Landslide," where Brown plots support for the Democratic and Republican parties in the early 1960s and, as in Remote Viewing, uses stippling to indicate equilibrium marshes:

I post this here for possible sync relevance, since marshes -- Thomas B. Marsh, Pokélogan, etc. -- have been a recent theme.