The following is intended as a template for action or a beginning point for a discussion that is long overdue.
Landscapes are more complex than most people realize. They can go seriously awry in a very short time. Undisturbed native plant communities are relatively stable and are able to respond on their own, as they have for millions of years…if the disturbances they suffer are relatively small. Unfortunately these plant communities have been decimated in urban and most rural agricultural areas severely compromising their abilities to respond in a positive and effective manner. The addition of invasive species to the region puts even stable, undisturbed plant communities at risk. Because we are not all ecologists, or even gardeners, what can we realistically do to stop or reverse this process of landscape degradation? The decline of our landscapes is linked to a long history of practices that have ignored the value of both our native and contrived landscapes, a belief in a right to ‘dispose’ of the land in whatever way we so choose and our denial that this destruction matters. We have done this through our land management practices, our designs and the uses of the land itself even those that may seem unrelated, many that have become automatic in our society and are directly related to how we live, work and play today in the modern world. Our active threat is inherent in the way that we do business. Our attempts at correction are, too often, limited to only slight modifications that do not put any undue ‘pressure’ on our local economy, business or the privileges that we have come to see as ours. We are a society that has, in short, become disconnected from the realities of life at the local level and what is required to support it. We see a limitless nature that is there for our use. Whatever we may need, we believe that we may merely buy from elsewhere, an elsewhere that is limitless though undefined.
To turn this situation around, or to make significant improvements, requires that we examine what we are doing now, that may be working against the goals that support life and landscape,…and stop. We have to stop doing the things that are working to continuously disrupt the ‘healthy’ functioning of the landscape. If we don’t do that then all of our attempts at improvement, all of our tweaking of our system, will come to nothing. We cannot ‘save the patient’ with good thoughts while they bleed out.
Land owners must step up to the task whether theirs is an undersized urban lot or several thousand acres of public land, whether they are a Parks organization or a transportation agency, or own a substantial corporate campus or a few parking lot ‘water gardens’. To dismiss the care of the land as a low priority that is off mission and so ignore, or under fund it, is a message to the public that such lands are dispensable. When these are large property owners, public or private, especially when under the care of government agencies, this is a powerful and destructive message. The policies, priorities and practices of today assure that our landscapes will continue to decline and because these are living systems, this decline will continue at an accelerating pace, each loss compounding the next.
Where to Begin, Stopping the Damage
Clearing, stripping or regrading the land is a typical first stage in developing our land, it is necessary, but land is often so cleared and then held over time in this state, sometimes for years, awaiting development. Other times land is simply ‘held’ in this state…with no clear development plan in the ‘wings’ or under consideration. It is often an economic decision to leave such landscapes in a ‘chronic’ state of disturbance. These sites are not ‘communities’ of plants. If planted at all they are done so simplistically with few species, poor coverage and without a thought to layering. Most of these landscapes are composed almost entirely of the opportunistic ruderals including many common weeds and invasives.
Nature abhors a vacuum. If you strip the soil and/or plant communities from the landscape, others will move in to take their place. If you attempt to maintain a ‘landscape’ free of plants whether it is an asphalt roadway, a graveled railroad right-of-way, an abandoned building site or a fence line, whatever plants are available on the site, that can tolerate the growing conditions, will fill the space. These plants form a large group known as ruderals. These are colonizers and include weeds as well as some of our ‘tougher’ more adaptable native species.
Ruderal plants have been ‘selected’ by the compromised conditions themselves that we routinely create and sustain around us. Previously, before the onslaught of weeds that we’ve brought with us and the continuous assault of disturbances we impose on our landscapes, ruderals were composed of only those most adaptable of our native species. Now they include our weeds. They are an effect of all of the forces and organisms at play in the landscape. These are the plants able to reach maturity, flower and rapidly increase through their ability to produce viable seed and/or to spread vegetatively via their roots, stolons, rhizomes or bulbs. The intricate and complex connections between species, the relationships within native communities, have been broken on disturbed sites. As species are directly removed others may be lost as a result of this absence, greatly simplifying the possible relationships. Ruderal species are more adaptable, less dependent upon complex relationships with other species. When these species and relationships are absent more complex species that we may plant there will require our intervention and support to continue so as not to be overwhelmed. When plant species are reintroduced care must be taken that their growing conditions are met and that they are planted into a matrix of other plants, that will more likely help sustain one another, these together will comprise a community that mimics native plant communities.
Ruderal species are held in the local soil seed bank and can remain viable for many years. Like our common weeds they too are opportunists. All plants are in fact opportunists, that if available will attempt to take advantage of an open niche. Obviously, if desirable species are not in the seed bank, they won’t be available to colonize open ground. The more compromised the growing conditions the more likely colonizers will be available ruderals and invasives. We see situations where landscapes having been buried beneath a heavy layer of English Ivy, that respond to its removal with the return of many natives that had been suppressed beneath this aggressive layer. These survivors have endured. Each species will vary in its ability to withstand such a wait. Any plant will lose their viability and succumb over time. But if these conditions improve for the original plant communities, as relationships are grown between plant species, soil and the many other organisms, other more desirable species may be supported if they are planted or moved to the site. The longer a site is managed in a way that it is dominated by invasives and ruderals, the more their seed will dominate the seed bank, again, something they are very good at. We tend to treat such sites similarly, managing them in ways that regularly re-disturb them perpetuating the conditions that are favorable to their continuation. It is a cycle that we have perfected and effectively prevents these sites from stabilizing and forming more desirable and effective communities. These sites remain open to invasion by other aggressive and undesirable weeds when they may arrive on site that is in a chronic out of balance state. Healthy sites with a healthy complex web of relationships are more able to withstand weed invasion and ruderal species will lose their competitive advantage as the community shifts the population in a more complex direction…if allowed to. Remember that invasives, because of their own aggressive natures, will always be able to invade a landscape.
It is in the nature of living organisms to modify the growing conditions within the sites on which they live and grow, casting shade, penetrating soil with their roots, capturing nutrients that might otherwise be leached away, altering humidity about them, effecting wind patterns on the ground, intercepting sunlight, modifying the soil chemistry and the composition of microbial life, effecting soil moisture levels and pH in the immediate area, adding to the organic content of the soil and promoting the aggregation of soil particles, in addition to their ‘contributions’ to the soil seed bank. Many plants exist together with other organisms sharing metabolites. Each plant does this uniquely in competitive and often mutually supportive ways with other plants creating niches for complementary species.
With the death or removal of anyone plant, all of these things begin to change as certain rot organisms appear in higher numbers breaking down the living tissues of the deceased over time, freeing their components for reuse (Rot organisms are always around as cells and tissues are regularly being sloughed off or replaced). Cutting and removing this same plant, which is common on disturbed sites, changes this decreasing available nutrients and the web of organisms that all play a role in this ‘recycling’ from life to death and back again. Removing the plants of an entire landscape does this on a drastic scale. Combining this with regrading the soil, the seat of this entire process, does this catastrophically. Such a disturbance breaks the entire cycle, perhaps most critically for life, the removal of the soil seed bank and the structure and composition of the soil itself. The microbial life, that is dependent upon what lives upon and within the soil, what decomposes there, can be radically altered or removed and, given the rapidity of its own cycling, may depend entirely upon re-inoculation from surrounding, intact, landscapes and populations to return, because it cannot survive alone in a dead and sterile soil. They are directly connected and essential for the health of each other.
This an extremely disruptive and destructive practice and evidences, on a more massive scale, some of the problems with our many routine maintenance practices that we commonly utilize on our conventional landscapes. These practices must stop if we are to ever reverse this process. Of course for this to happen we must come to the understanding that what we are losing is of indispensable, even critical, value.
Some Guidelines –
1, Intact, natural landscapes will be identified, left undisturbed and protected
These are both sanctuaries for native species and reservoirs that support the healthy functioning of the same. These will be protected, actively managed in ways that minimally disturbed them to keep them free of invasive species and limit the human uses that may threaten them.
Size of these areas matter. Just as we know that wildlife depends upon intact landscapes that provide habitat necessary for their survival, we know that these must be large enough for the many species. Isolated healthy landscapes are under a great deal of ‘weed pressure’ from the surrounding degraded landscapes and will suffer over time. They will likely fail without our active defense. Anyone doing maintenance knows that it is the edges that must be watched the most closely for weed invasion. Weed seed and plant propagules move onto sites, working in from the edges, sometimes covering significant distances via water, wind, vehicular transport or by hitching rides on us or animals including our pets and birds that may carry seed considerable distances. The edges of landscapes are also most subject to human disturbance in the form of compromised growing conditions and threats to the immediate survival of plants. Biologically, edge landscapes are more dynamic than are those within having more variable growing conditions and broader species availability. Small and long narrow landscapes are under tremendous pressure to ‘change’. While developing property, leaving small pockets and edges of undisturbed landscape will be a failed strategy without a commitment to actively fund and maintain its healthy continuation.
Urban landscapes have suffered massive disturbance historically and, generally, are designed and maintained in a manner that ignores the natural processes active within the landscape. 2, Disturbance of all urban landscapes will be avoided or minimized to contain the damage. The two major concerns are land that has been cleared for redevelopment and is in limbo for an indeterminate time and landscapes that are being maintained routinely in a manner that keeps them in a chronic state of disturbance. Both of these allow landscapes to serve as incubators and reservoirs of the seeds of weeds and invasives to both ‘infect’ other landscapes and render them more difficult to bring back to a balanced/dynamic and sustainable condition. Both of these situations need to be minimized, transition cleared and graded sites to their finished state quickly to limit weed seed production and to convert sites that are maintained in a disturbed condition perpetually into stable, viable and layered plant communities.
Property/landscapes are often maintained in a chronic state of disturbance to save money, but this only saves money for the property owners. These deferred expenses are transferred to all other adjacent owners which can increase exponentially over time as weed and invasive seed ‘deposits’ increase. The effects and ‘pressures’ accumulate across urban areas and then radiate out across rural areas, which are maintained in a chronic state of disturbance because agricultural landscapes are themselves simplified, on out into the surrounding natural areas via our transportation corridors and our own movements to and through them.
3, Disturbances are defined as any activity that disrupts the growth or natural cycling of energy and life in the landscape, that lays bare any piece of soil whether resulting from grading or cultivation practice, or disrupts/removes a layer of the landscape, ground, middle shrub or tree canopy layer. This is necessary because disturbances compromise the integrity of landscapes/plant communities with regards to invasion by invasive plants and common weeds alike.
3a, Certain landscapes, e.g., those serving a community purpose such as for recreation, sports fields and passive recreation, or as transportation corridors, food production/agriculture and the growing of ornamental gardens, may ‘require’ more ‘disruptive maintenance strategies’. Because these landscapes serve a necessary purpose in urban communities the creation and maintenance of these with their limited and focused plant palettes, which by design and intent may be incomplete plant communities, are unstable and will require cultivation which would otherwise be considered ‘disruptive’. It shall be the owners responsibility to keep such landscapes in a healthy productive state, actively managed, to limit the growth and control, there on, of common weeds and invasives alike. The ‘best’ strategy, to meet the broader community priority, may be to utilize viable plant communities, in the form of buffers, to whatever extent possible in order to minimize ‘pressure’ on adjacent landscapes and disruptive practices as well. Some ‘disturbance’ will be necessary to safeguard the infrastructure itself and in order to operate it safely and effectively.
3a.1, Turf is a societal need in urban areas that increases with human populations density. As an unstable monoculture these kinds of landscapes require otherwise disruptive practices. People need open public spaces for passive and active recreation and casual interaction. Turf is often the best surface for this, but as a living, albeit limited living landscape, it too has limits to the intensity of use. Healthy turf requires active management including irrigation, fertilization, compaction relief and weed control if it is to maintain its social benefit. Part of this derives from the fact that it is composed of species/varieties that are very limited occupying a very thin ground layer which is reflected underground by an equally shallow rooting layer which limits its ability to extract soil moisture, increases the loss of nutrients through percolation and leeching and leaves it vulnerable to invasion from an incredible number of weeds able to utilize many open niches. It is also susceptible to soil compaction by any use, the intensity of which increases with our use of it which in turn limits rooting depth and the health of the grass. Any lack in its cultural care increase the likelihood of weed invasion many of which are capable of invading adjacent landscapes. When it comes to turf, care deferred, is irresponsible. Turf needs regular irrigation during our summer months to maintain its health or it will weaken. This problem is ubiquitous. The social value of such turf is greatly reduced and puts additional weed pressure on other landscapes. If you want to eliminate the problems that can come with regular turf maintenance…get rid of the turf and provide a hard surface that can withstand the use. Of course this comes with entirely different set of problems.
3b, The reclamation of compromised/disturbed landscapes into those described in 3a or to be converted into landscapes of more balanced plant communities, either based on native models or attempts to create ‘new’ such landscapes, those with more ‘innovative’ plant communities, on degraded sites in response to their changed conditions, may utilize more disruptive strategies to clear and control the weeds and invasives that may be established on these sites to give these new landscapes a better chance at success. Such landscapes will require regular monitoring to insure that maintenance and further development of the plant communities will be responsive to the changing conditions. Success of such landscapes are dependent upon the new plant communities out growing the weeds and invasives previously established over time. As many weeds/invasives may have seed in the soil seed bank that can remain viable for many years, vigilance is required.
Property lines are among those most problematic landscapes to maintain in general. In the cases where these edges bound roadways and other transportation corridors including railroads, these effectively create passageways for the movement of weeds into and through urban areas. 3c, Edges are not exempt from the requirement to control weeds. These are commonly fence lines or open narrow margins often abutting buildings and are of limited ‘use’ sometimes with poor access for performing maintenance sometimes with neighbors who neglect their landscapes and so continuously infect the adjacent landscapes. These landscapes will often require a coordinated approach which can include complementary/supportive plantings and an active maintenance effort. It may be that the ‘best’ treatment will be herbicidal when strips are so narrow that no effective plant community is possible.
4, All property owners, residential, commercial, institutional and governmental will be required to be responsible stewards. Property ownership comes with certain rights that are advantageous to the owner. This implies a balancing burden of responsibilities for any impacts that their properties have on those of others and their owners. As owners are quick to take advantage of the benefits conferred upon their properties as a result of the properties and actions of others, they are therefore also responsible for the negative impacts that their ownership and maintenance imposes on the rest…this includes those of the landscapes themselves on their properties. Profit ‘earned’ or savings ‘accrued’ at the loss of others helps create the scenario we have today and leads to the rapid degradation of the overall landscape, a situation that is untenable over even the mid-term. Those property owners who are working to be responsible stewards are put in an impossible, and expensive, situation as the pressures increase on their own landscapes through no fault of their own. Such deferral of responsibility by negligent landowners is unacceptable and is a clear indication of their skewed priorities and/or their lack of resources to properly care for their landscapes, which means that actions should be taken to transfer ownership to more responsible owners, or that they are simply ignorant of the negative impacts of their ownership and management. In the later case, education and technical assistance should be made available so that they can improve their practice.
4a, Leadership is necessary in the form of both responsible government action with their own properties and in the form of public education and outreach. Positive supportive programs addressing this issue require a larger commitment. Purely punitive actions in the form of most of our current nuisance ordinances, is insufficient and ineffective as is demonstrated by this problems worsening across the area. Small underfunded agencies like our soil and water conservation districts, must be supported by the actions of all other government agencies who own land.
Every owner has their own set of priorities that moves them toward their goals and mission. Land ownership is often a prerequisite to that mission. Owners are also participants in the larger society, membership within which, confers certain benefits, whether they are recognized or not by owners, be they individuals, businesses, institutions or the governing bodies themselves. It is incumbent upon the owners to uphold their end of the ‘social contract’ which can reward them handsomely, a responsibility that should they shirk it, carries with it a negation of society’s responsibilities to them which would negate an owners profit. It is therefore the property owner’s responsibility to fulfill its obligation simultaneous with its pursuit of its own priorities. One cannot be separated from the other, but this is what has been happening for most cases since the adoption of the capitalist economy and the industrial revolution. Profit has been valued above the health of the landscape upon which we all ultimately depend.
5, Invasive plants, sometimes called ecosystem disruptors because of their ability to invade natural undisturbed sites displacing native species, shall be monitored and controlled. It is the property owners responsibility to have a plan in place, which will create minimal additional disturbance and to be working towards its successful completion. At minimum owners will control/limit the spread of seed and plant propagules from these plants on their sites to others. Government shall lead by example and through its support of property owners as they work toward this goal.
6, Built landscapes, unless they serve the purposes described in 3a above, shall attempt to mimic natural landscapes that may have occurred on similar sites presenting the same conditions. If the site conditions are so altered that they do not exist naturally/locally innovative plant communities can be planted that meet said conditions in a way that will require minimal maintenance and minimize the burden they put on adjacent landscapes. There are resources available in the form of books, models and examples of this kind of work developed by individuals, conservancy organizations and forward thinking agencies today. Policies, programs and practices need to remain somewhat fluid as this entire approach is ‘new’ and unfamiliar for us. We cannot afford to continue working at cross purposes. Destructive practices must be ended. Monitoring and evaluation are essential. Practices need to responsive to what we learn. Above all the danger inherent in our current practice must be recognized and our responsibility owned.
Nature adds complexity to landscapes over time. Any ‘new’ landscape whether the result of an intense forest fire, a landslide, an obliterating volcanic eruption or the calculated stripping and grading of a site for development, begins at a ‘zero’ point and builds from there. Those plants in the soil bank will colonize first if they are tolerant of the current growing conditions…if not, seeds from adjacent property will be the first colonizers. As conditions modify over time niches will be created providing support for species previously not possible and, in turn, taking physical space and resources from plants that had previously occupied ground. Compositionally simple landscapes are unstable. A soil seed bank ‘contaminated’ with aggressive weeds and invasives can undermine the more natural colonization and development of such a landscape toward a diverse and balanced plant community. We are a part of the landscape and can play a pivotal role in either its destruction or recovery. The creation of plant communities, and their enhancement over time by us, is a recognition of this process and requires our close attention.
A beginning point is the relatively undisturbed landscapes around us. Deep soils in our region support complex landscapes that range from grasslands and Oak savannah to mixed woodlands and forests while others center in and around water. Planting them with a limited and simple palette, especially in a one or two layer scheme, will doom many of them to failure or require a never ending regime of intensive maintenance. Including in your plant palette those species and varieties that originated from regions with climates different from ours will do the same. Failing to recognize how severely altered growing conditions may be, especially in urban areas, which include everything from soil depth, toxicity and composition to exposure and the content of the soil seed bank, can doom a landscape to inevitable decline and the constant futile tinkering that many of our landscapes endure today. Designing and maintaining landscapes of viable plant communities is an entirely different approach to the landscape. There is no one size fits all approach that will be successful, no single simple palette of plants to be learned to make field staff effective, no simple strategy of shear, mow and blow with each plant located discretely within its own slotted space with everything else cleared away. Nature does not work this way. Ignoring this requires that we expend a great deal of our energy and budgets to maintain these kinds of landscapes into the indefinite future.
As our urban areas expand so do all of our landscapes and the financial burden that they put on us to keep it all going. Inevitably, we drop the ball, we prioritize and cut loose lower value landscapes, adding to the problem and pressure on all of the rest. We are also suffering a ‘cultural’ problem of our own a huge portion of our population having little understanding or relationship with the natural world.
This is not an irresolvable problem. This is doable…but to be successful requires that we take an entirely different approach. There are individuals and organizations attempting to do this, though they are on relatively small islands of land, most notably these include land trusts and conservancy organizations, soil and water conservation districts and to some extent, programs within existing government agencies, but this is huge, societal problem, that is beyond their reach. There is little discussion outside of these. State and municipal agencies struggle with their own conflicting politics, with budgets divvied up based on priorities often set by those largely ignorant of what I’m speaking of here. Such a system dooms us to more of the same and an ever accelerating decline. There is very little public discussion of the problem as those of us already committed talk amongst ourselves and vested interest push the status quo. It is unlikely that Jeffersonian yeomen farmers, connected to the land, will step up, because, as a class, they are so small. It is up to us, the gardeners, small farmers, ecologists, forward looking parents and outdoor recreationalists who are beginning to understand that the landscapes out there, which we enjoy and are dependent upon, are coming under ever increasing pressure from users and all of the pressures I’ve spoken of above. We cannot ‘tweak’ our way out of this problem. It’s sources are structural. If we and these landscapes are too survive then we have to effect real changes…we have to begin.
For a more detailed look at the problem see my earlier postings:
For a good introduction to the use of plant communities in built landscapes see, Thomas Rainer and Claudia West’s, Planting in a Post-Wild World: Designing Plant Communities for Resilient Landscapes, Timber Press 2015.