A possible popular and broadly accepted definition of an invasive species is a species which may cause or is causing or is contributing to economic, environmental or aesthetic harm to the environment or an eco-system. Even this sweeping definition is complex, reflecting the challenges of finding agreement among stakeholders as to intermediate solutions and end-system state objectives. This obscuration of the definition by competing stakeholder goals such as complete restoration of a local or regional eco-system versus the traditional impulse to regulate, replace and renovate a landscape creates a dynamic undercurrent when the parties attempt to agree on possible jointly-held positions or short-term solutions.
The natural area manager or conserver is seeking to protect, enhance or preserve a fully functioning eco-system. The natural system is, by at least part of a definition, self regulating. In the complexity of the stable system may be found a broken symmetry. The reflection or result of an unstable but uniform, and ecologically symmetrical system, includes and sustains organizing hierarchies of time and process. The simple result is a system which is not simple in its functioning and is built upon interlocking random events. The diet of an herbivore is controlled by biological abilities to ingest and process certain chemistries, and so is a defined controlled variable; the random event which directs herbivore towards or away from a digestible bio-mass is random. The traditional landscape designer or architect is attempting to restore syntactic literacy by replacing the natural area’s hierarchical and temporal complexities and perceived randomness with a symmetrical system. The traditional landscape trades functional stability for domain uniformity.
An invasive species may be seen as a symptom of a stressed or failing, dynamically complex, self perpetuating and self regulating environmental system. Or, it can be seen as part of the process of returning to a symmetrical state. The invasive species is also representative of the loss of biological granularity; the impacted system is in the process of returning to large structure domains and ultimately to system uniformity. One way to reconstruct symmetry in a finely granulated system is to apply heat. The increase in climate temperatures are, to some extent, impacting and furthering the spread of invasive species. As heat is applied, the system will move to a point of uniformity as hierarchies of process collapse and are aggregated. For example, as the food chain within a system becomes limited and or broken, the number of species will become smaller.
Traditional land use options all result in the application or addition of heat to the surrounding eco-system, though at differing levels and rates. Conservation or mitigation efforts are at some level attempts to maintain an equilibrium measured by sustainable diversity. Thus, two major stakeholders, horticulture/agriculture and land managers/environmentalists, find themselves at unspoken and, mostly unrecognized, high-level, philosophic odds.
Therefore, we find ornamental gardeners attempting to introduce “horticulturally” controlled and defined diversity which may require the addition of hydrocarbons in the form of fuel or fertilizer to off set the removal or collapse of the previously existing complex system. Meanwhile, using accepted definitions as to natural, domesticated, and cultivar, conservationists are in direct opposition to the “cultivation” of species imposing immediate short term cost constraints upon production. A controlled collection of native seed is sown to produce mitigation plants, however only three generations of collected plants would be qualified as native or natural, the fourth generation being considered domesticated.
The short term costs versus long term costs mirror the small/fast activities of a functioning system versus the large/slow events. A stable system with its broken symmetry is complete with various interwoven short and long term processes. The activities of human tend to influence random events with in the time horizon of the human species; I suspect that this is a general constant; that all species respond and interact based upon the temporal limits of the particular species. Accordingly, bacteria are not reacting to human time level events let alone geological events, and humans are as a rule not responding to eco-system level events such as climax succession. And, therefore, the system is not responding directly to human level time boundaries.
We are faced then with the challenge of life, which is to stay alive, a short term decision constraint, while not destroying the same system which provides the opportunities needed for the same life and are long term decisions. We have a balancing act full of pitfalls filled with unintended consequences. We find ourselves again in the grip of the wicked inconvenience of invasive species.