The Use of Passive and Active Approaches in Restoration Projects

Introduction to Winter 2016 Ecesis, Volume 26, Issue 4

Welcome to the Winter edition of Ecesis, SERCAL’s quarterly newsletter on contemporary restoration issues. This issue features projects with passive and active restoration elements. What criteria should be considered when determining if passive methods will meet success criteria? Costs, scheduling, unintended ecological impacts, and public perception all affect a decision of whether or not — and to what extent — a restoration project might be executed with more passive means. 

I first became intrigued with the concept of passive restoration many years ago from a gardening article written by a respected British gardener. She described her success in reclaiming abandoned, weed-covered roadways by converting them to native species cover. Her method was elegantly simple in its way of obtaining impressive results without the pomp and circumstance of heavy equipment or herbicide spraying so common in today’s large-scale projects. The method consisted of approaching a large infested area in a methodical manner — beginning on the edge of the area to be cleared, she tenaciously worked a five-foot wide swath with hand tools to remove all invasive vegetation. The invasive-free area was meticulously maintained as she worked additional swaths at regularly scheduled intervals. The author reported that the simple removal of aggressive competition created the conditions for natural recruitment of regionally indigenous species which eventually populated the cleared areas. Such basic, “low tech” principles, given the appropriate site and overall project conditions, can benefit ecological restoration objectives and should be considered…when time allows.

Of course in our current environment of regulatory compliance, success criteria with concomitant schedules, etc., many practitioners don’t feel it is practical — nor is the idea consistently entertained with eagerness by regulatory agencies — to proceed in a passive, and typically more time-consuming process. Despite the fact that passive approaches are typically more cost-effective than active approaches, there’s a common perception that the higher the project price tag, and the more effort expended, the more successful the project will be.

There are other ecological system recovery concepts to consider when deciding between passive and active approaches. For instance, if an ecological system has been affected by a man-made disturbance, oftentimes it is only a human-engineered intervention that will bring it back to its previous condition… Nature isn’t always the best-equipped to process or resolve mankind’s most egregious assaults, especially in terms of human timeframes. In this sense, it could be argued that aggressive, active treatments are the sole option.  

Perhaps there are times that the natural world could be allowed to process on its own terms when other human criteria can tolerate it. I urge you to read through these projects and think of the projects on which you have worked and are currently working, to explore whether a more passive approach could alternately meet the project’s objectives and long-term success criteria. — Carol Presley, Carol Presley Consulting