Some plants are just a little too weird

 Echium

Gardeners can’t help their obsessions with strange-looking plants. And usually, with the hard-core gardeners that I know, the weirder the better. But new research suggests that these far-flung oddities do not benefit much in the environment. Doug Tallamy, professor entomology at University of Delaware, and his student Karin Burghardt, conducted a three-year study to see how herbivores responded to planted yards full of either exotic or native plants. Not surprisingly, there was not as much insect diversity found on the exotic plants as compared to native plantings. They further found out that there were even less species on exotic plants that did not have a close native relative. For example, exotic Norway maples are kin to our native red maples, and shared nearly similar insect diversity. While the far flung exotics that had no close native relative supported little life. Burghardt noted that “If you think about it, you're driving around the suburban environment, and every time a new development goes in, you have a lot of decision making happening as to what plant species are going to be planted around those properties. If we do all that landscaping with non-native plants, are we limiting the wildlife and conservation support system that could be available within that given plot of land? What the gardens we constructed for the study are trying to replicate are landscaping decisions that people might make if they wanted to support native insect communities that in turn support much of the diversity around us.” Their paper was published in the October 2015 issue of Ecology Letters.

Conserving Vacant Lots in Detroit for Stormwater Control

One of the more impressive ideas for reusing vacant land in downtown Detroit is to create gardens for stormwater control. An article in the Detroit News by writer Kim Kozlowski (December 14, 2015) states that the Detroit Water and Sewerage Department and the Detroit Landbank Authority have partnered to utilize a few  open lots for rain gardens. Rain gardens store water temporarily before releasing it to city stormwater systems. And this is important in cities like Detroit that have had problems with overloaded storm systems that can dump urban water, and raw sewage, directly into the Rouge River. In 2014, polluted urban runoff from Detroit and its surrounding areas created undrinkable water supplies for parts of Michigan and Ohio. Joan Nassauer, professor of landscape architecture at University of Michigan, is leading the project’s effort to slow the urban runoff. Nassauer states in the article, “If during a storm we can keep much more water here just below the ground, that reduces the pressure on a city’s system and so there won’t be a big untreatable amount of water that comes into the system” (Article available from the Detroit News online at http://detnews.com/)

The Art Garden, Mississippi Museum of Art

Edgeland Excerpts: Is Native Purity a Viable Option?

Quoted from Dr. Colin Meurk: “But, what is “wild?” There is an appetite again for “rewinding” and using “cues for care” (Nassauer) in urban environments to make this acceptable. The niche envelopes can be as surely defined in these contrived ‘wild’ urban environments as in the real wild. With many environmental stress/disturbance combinations, native species will individually survive by chance at some points and places, in combination with some (weakened) exotic species, then reproduce and eventually find their ‘natural’ position in the gradients provided as self-sustaining populations. That may be the future of many lowland, open habitat herbs. Then invertebrates, birds and lizards will find these plants and establish their ‘natural’ interactions. Meta-populations of such plants may form on roofs, walls, pavements, rock gardens, lawns etc. These habitats can be seen as forming an archipelago in urban environments!"

Dr Colin Meurk is a senior ecologist at Landcare Research, New Zealand. Quotation from Global Roundtable Green Form and Function versus Green Nativism at the Nature of Cities.com (http://www.thenatureofcities.com/2015/11/05/green-form-function-versus-green-nativism-in-changing-urban-spaces-full-of-novel-ecosystems-and-natural-assemblages-is-native-purity-a-viable-option/)

It's Better to Leave Your Leaves

Experts from the National Wildlife Federation (NWF) reported that it's definitely better to leave your leaves, where they lay. Gardeners and landscapers know that plants grow better in mulched beds. Decomposing leaves contribute nutrients back to the soil, screen sunlight from hitting plants roots in summer, and protect from moisture loss due to evapotranspiration. But wildlifers are interested in the ground habitat that leaves provide. NWF says that worms, mammals, amphibians, reptiles, and many insects depend upon leaf litter in which to lay eggs or hide. Randall Hitchin, University of Washington Arboretum, says he rarely rakes leaves because "it changes the habitat, and makes it unfriendly for (insects)"(Dan Cassuto, KING 5 news, Nov. 3, 2015).  Areas that are currently in lawn grasses can be easily converted to planting beds by simply raking the leaves to areas underneath trees or around shrubs. Thick layers of leaves will choke out the existing turf and become soil habitat in no time. And the surrounding trees and shrubs (and critters) will immediately benefit.

Ovenbirds Take to Forest Fragments

 DickDaniels (http://carolinabirds.org/)

“And comes that other fall we name the fall.

He says the highway dust is over all.

The bird would cease and be as other birds

But that he knows in singing not to sing.

The question that he frames in all but words

Is what to make of a diminished thing.”

                --Robert Frost, The Oven Bird

Ovenbirds (Seiurus aurocapilla) are LBB’s (little brown birds) that are seen foraging for food on the forest floor across Canada and the eastern United States. While their breeding range is in the northern United States, they overwinter in the southern U.S. and Mexico. Ovenbirds breed and nest in older deciduous or evergreen forests and are rarely found in urban environments. Except for suburban landscapes.

In a paper entitled “Forest Fragmentation Effects on Ovenbird Populations in the Urban Region of Eastern Massachusetts, USA” published in Urban Habitats (2012), authors Morimoto, Frankel, Hersek and Wasserman found that large residential lots with forest cover can effectively serve as nesting habitat for these forest birds. The study notes that forest cover greater than 40% and small woodlots close to larger tracts of forest with high connectivity reduces edge predators such as cowbirds, which often plague the ovenbird’s nests.

The study concludes that “urbanization accounts for the majority of developed land in many areas in the Northeast (e.g., Steel 1999). Given this trend, it is of critical importance to recognize the value of the remaining forested habitats in these regions and to manage these landscapes in ways that will maximize their benefits to natural communities and species of interest. We recommend that municipal leaders, land managers, and planners take account of geographic location and regional landscape context when interpreting and then applying results of scientific studies to the management and conservation of viable bird populations in urban regions and elsewhere" (Morimoto, Frankel, Hersek, and Wasserman 2012). 

Book Excerpt: Planting in a Post-Wild World

"Tomorrow's designed landscape will be many things--more plant driven, site responsive, and interrelated--but one thing it will not be is stylistically the same as its predecessors. It is perhaps easy to assume that plantings layered with a diverse mix of species would be necessarily naturalistic in style. In many cases, this is true. But gardens of any style can benefit from applying natural principles. Whether the planting is formal or informal, classical or modern, highly stylized or naturalistic does not matter. What matters is that plants are allowed to interact with other plants and respond to a site. This is the essence of resilient planting."
--Thomas Rainer and Claudia West (2015), p. 243

In the Weeds

 Winged sumac

Nice article by Nate Berg in the Sept. 2015 issue of Landscape Architecture magazine on the urban ecology/design work of Future Green Studio, from Brooklyn, New York. Several reclaimed-use projects are featured, including an event space called Nowadays. The design team, led by FGS principal David Seiter, kept the pre-existing honey locust trees that were sprouting through the cracked pavement; and then replanted other urban “weeds”: including sumacs, birch, aspen, goldenrod and Queen Anne’s lace. Seiter is quoted as saying “It’s rooted in a conceptual understanding of landscape and site to reveal the latencies in the site and think about how they can be woven into a future designed environment” (Berg, LAM, 2015, p. 64).

Find out more about Future Green Studio at their company website at http://futuregreenstudio.com/

About their firm: “Our approach is reductive – through analysis, we scrape away and unearth the layers of an existing site to reveal its inherent value and beauty. We develop a thorough understanding of its historical, material and spatial conditions so that we can optimize the often overlooked social, ecological and economic assets that lie dormant within it. The goal of this approach is to reveal the nuances of the urban landscape in subtle, poetic ways; awakening the user to the complex ecology of our cities.”

Cities need natural systems

"Urban spatial design is a key factor shaping how urban dwellers relate to the landscape (Matteo et al., 2014.); therefore we must rethink and redesign urban areas to feature natural ecosystems and the intertwined processes of natural and cultural history."

Beery and Jonnson, 2015, "Inspiring the Outdoor Experience: Does the Path Through a Nature Center Lead Out the Door?", Journal of Interpretation Research, Vol. 20, No. 1, p. 67.

Urban Land Use and Landcover Types

Single-family residential, mixed-family residential, mixed use, and industrial landuse when compared with urban forest, urban grass, paved urban, grass, and forested landcovers (Alberti 2007)

 

 



Forested landscapes tend to be found more often in single-family residential areas than in other land-use types, according to a 2007 paper by Marina Alberti, a professor of urban and environmental planning in the Department of Urban Design and Planning at the University of Washington. In her paper entitled Ecological Signatures: The Science of Sustainable Urban Forms in Places (19(3)), Alberti uses GIS data to identify the primary ecological signatures of urban development. As shown in her graph above (2007), an analysis of the Seattle metropolitan area shows that single-family residential (SFR) ranked high in urban forests and conserved forests but lower in impermeable paved urban surfaces (concrete and asphalt). Mixed-family residential (MFR) and mixed-use (residential and commercial zones) tended to have less forests but more urban lawns. Industrial landscapes tended to be highly paved with some grass and little forested land. As your community grows and expands with residential, commercial, or industrial properties; what impacts does that expansion mean for urban biodiversity?

Exotic vegetation types in urban areas are linked to longitude

Colonial Williamsburg, VA

It seems that the fruit does not fall far from the tree. In a paper published in Urban Habitats (Vol. 1, no. 1), researchers Steven Clements and Gerry Moore studied 8 U.S. eastern cities and compared the diversity of both native and non-native plants. Looking at Boston, New York, Philadelphia, Washington, D.C., Detroit, Chicago, Minneapolis, and St. Louis, they found that these cities averaged 65% native trees to 35% exotics. For the native trees, they found similar clusters of species in the Boston, New York, Philadelphia, and Washington, D.C. area; and another cluster around Detroit, Chicago and Minneapolis. For the non-native trees, they found the most similarity around Chicago and Detroit, and New York and Philadelphia. Clements and Moore surmise that the exotic tree clustering is longitudinal, and "most likely the result of the history of plant introduction in North America." The eastern seaports have the most non-native species which declines significantly as one moves westward. They also note that exotic species have more time to become established with older cities. Similar observations can be seen along the Gulf Coast near New Orleans and Mobile, though it is more latitudinal.

Detroit-isms

Detroitism: "the fetish for crumbling urban landscapes mixed with eccentric utopian delusions, 'where bohemians from expensive coastal cities can have the $100 house and community garden of their dreams." -- John Patrick Leary, Guernica magazine, 1/15/2011
 (Image by Michael Yun)

Michael Yun makes an interesting case in his master's thesis at the University of Michigan for Detroit's ample vacant lands to be restored to the vast prairie that it once was. Entitled "Alternative Uses for Vacant Land in Detroit, Michigan", Yun takes a look at the potential rejuvenation of derelict land. Completed in 2008 under Professor Joan Nassauer, Yun notes that the existing open lands in Detroit help to filter stormwater, harbor native plant and animal species, and serve as greenways that run through the city-- even better than what the previous houses and urban landscapes once did. He proposes for areas that have four contiguously vacant properties be converted to prairie, with a 30 foot mown buffer between the lots and adjacent properties. This would provide a safe distance so that occasional prescribed burns can maintain the prairie plots (or if it is a dilapidated structure, can burn the prairie and eyesore all at once). Yun extrapolates how this approach could be applied across the city-- which seems unlikely--but even if prairies were restored upon a few small plots, it would reduce the mowing needs and add a much-needed landscape integrity once again to portions of the city.  Believe me, anything would look better than the current institutional-looking mown vacant plots. His study raises more questions than answers, but Yun's motives are clear when he writes "Could benevolent acts of restoration begin to heal the community even if the initial physical changes seem modest?  Central to the value of this proposal is balanced consideration of both ecology and culture, and a belief that there is an underlying symbiosis of the two.  Compassion, benevolence and healing are qualities that will positively influence both.  In this sense, humble actions toward repair are the necessary first step."

Reclaiming the New Orleans Arts District

Use Plants with a Punch

“Modernism is efficient because it aims for simplification. The central assumption is that technological solutions are universal, and so are independent of social context. This is what makes it appealing—mass production for us all. But modernist thinking inevitably leads to arrogance about the social and natural world.” –Tim O’Riordan, Susanne Stoll-Kleemann; Biodiversity, Sustainability and Human Communities

 (Kiley landscape, Chicago Art Institute)

Dan Kiley was a prominent 20^th century landscape architect that represented the height of modernism. His designs complemented sleek modern architecture and were clean, gridded—and mostly bereft of plant biodiversity. This use of mass plantings of the same species were common to Italian, French, Modernist and Minimalist traditions; and still influence landscapes today. Many city landscape ordinances promote biodiversity in plantings by encouraging the use of multiple species—mostly to prevent urban forestry disasters that occur with single-tree use (Dutch elm disease, Emerald ash borer, etc.).

Ecologists have documented the decline of native plant species diversity in urban areas as well. As shown in the chart below, McKinney (2002) gleaned from the available literature these observations:  that species richness declines the closer one gets to dense urban areas, and the urban biota changes as well. 

Zipperer and Gunstenspergen did their own empirical research by comparing both native and non-native species richness in five community gradients. Their conclusions showed a slight revision to McKinney’s model, one that shows native species richness declining as it approaches the urban core, and non-native species increasing as it approaches the urban core.

To enhance native urban biodiversity, US federal agencies (EPA, USDA, and DOT--in some states) are promoting the use of native plants; as well as NGO’s such as the National Wildlife Federation and Audubon. Wilde, Gandhi, and Colson (2015) propose that landscape plants (the ones that are primarily used in urban areas) should be bred with ecological function. Many landscape plant species are bred for form and ornamental characteristics (larger or more flowers, fruit, or other showy aspects). Similar to our shiny modern grocery store fruit-- taste and nutrition are bred out, but consumer curb-appeal is in. Wilde et al propose not only to scale up the use of native plants in urban landscapes, but to ensure that their genotypes also include the pollinator services and genetic diversity of their rural cousins.

Blogger Feature: The Nature of Cities

"The mission of The Nature of Cities is to promote worldwide dialog and action to create green cities that are sustainable, resilient, and livable. The TNOC community comprises a broad diversity of people, from architects and designers to scientists, from practitioners to entrepreneurs—pursuing transformational dialog that leads to the creation of better cities for all.

TNOC is a virtual magazine and discussion site on cities as ecosystems. It is a global collective of contributors, an essay, long-form, media,  and discussion site—an idea hive—devoted to cities as social-ecological spaces, ecosystems of people, buildings, open spaces, and nature. We believe that cities are human habitat, and that design with nature and public open space at the metaphorical center is key to urban resilience, sustainability, and livability.

Founded and curated by Dr. David Maddox (Urban Oikos Partners LLC, New York City, david.maddox@thenatureofcities.com. (With thanks to Mike Houck of Portland, Oregon)"

Find his excellent blog at http://www.thenatureofcities.com/

Somewhere in San Francisco

Pollinator Friendly Lawns

You could say that I am not a big fan of lawns. Oh sure, I love to play a game of football or walk the dogs on some green turf. But lawns are the landscape default mode for most human habitat--college campuses, city parks, subdivisions, and businesses. You will find lawns even where they aren't really necessary, mostly because we feel compelled to control nature. Rachel Carson once wrote that "the control of nature is a phrase conceived in arrogance, born of the Neanderthal age of biology and the convenience of man." She's right, we cannot control nature without feeling its aftereffects. 

I have removed significant amounts of turf from very place that I have ever lived and gardened upon. That goes for most projects that I have worked on as well. At my previous home on the Gulf Coast, I drowned 60% of the existing lawn area by deeply burying it in pine needles from the 17 mature longleaf pines on my property. To build my beds, I simply raked paths in the pine straw. Within a few short years I had effectively killed the lawn underneath and even began to build an organic layer. All that I had to do was to plant directly into the pine straw. I reduced two and half hours of weekly mowing and edging to about thirty-five minutes of sweat. 

But I noticed in lawn that I did keep, a wealth of native and exotic wildflowers grew in it. And if it was too wet to mow in some weeks, I had a healthy and beautiful wildflower garden that resulted. I stopped mowing when the lyre leaf sage came into bloom (Salvia lyrata), and mowed when their seed dispersed, ensuring new blooms and plants for the following year. I even did a species count once and identified around 15 species in a square meter. Not bad in biodiversity terms. 

Some herbaceous plants will grow quite well with regular mowings of the lawn. Below is a list of species that are turf companions, will bloom and benefit the pollinators in your neighborhood.

Native species of grass companions:

• Blue eyed grasses (Sisyrinchium, several species) not a true grass but a member of the iris family, with pretty blue flowers
• Cinquefoils, (Potentilla). Similar to wild strawberries
• Wild strawberries (Fragaria, several species). The five lobed leaves of this and those of cinquefoils are very similar in appearance
• Yellow violets (Viola pennsylvanica). A few other species of violets are also native
• Spring beauties (Claytonia spp.)
• Wild geraniums, crane’s-bills (Geranium spp.)
• Azure bluets (Houstonia caerulea)
• Speedwells (Veronica), with several species, some native others introduced
• Wood sorrel (Oxalis acetosella), used as ground cover by some gardeners
• Smartweeds, knotweeds, many species in the genus Polygonum; some are small enough to do well in lawns. Some species are native and others introduced
• Asters (Symphyotrichum spp.) are great in the fall. Some grow rather tall, better for a meadow than a lawn; but if mowed not too frequently, they can do well and bloom heavily inviting many species of pollinators
• Chickweeds include two genera: Cerastium and Stellaria. They are also known by several other common names; some species, such as field chickweed, (Cerastium arvense) and star chickweed (Stellaria pubera), are native. They are small enough to do well in lawns

Non-native species of grass companions:

• Clover, (white clover, Trifolium repens) a European plant very well established in the United States. Grass-seed mixes used to include it. It is highly beneficial because it fixes nitrogen, thus enriching the soil. Newly developed herbicides killed clover, along with the undesirable broad-leaved weeds, so it was declared a weed by the gardening industry and removed from grass-seed mixes. A few species of clover are native to some regions of North America and it may be possible to grow them as grass companions
• Creeping thyme (Thymus serpyllum) has sometimes been used as ground cover
• Chickweed, also called starweed, winterweed, satin flower or tongue grass (Stellaria media), is not native. Its seeds are eaten by some birds, hence the name chickweed. It has very small, star shaped flowers
• Gill over the ground, or ground ivy (Glechoma hederacea), is rather pretty but it tends to become invasive
• Dandelion (Taraxacum officinale) is among the non-native invasives which you may not want to see around but it is so widespread that perhaps we can’t do much about it

Thanks to the above great grass companion list by BY BEATRIZ MOISSET. You can find her article at http://nativeplantwildlifegarden.com/pollinator-friendly-lawns/

Blogger Feature: Marginal Nature and Urban Wastelands

Check out this interesting blog on marginal nature. Its author, Kevin Anderson, states in the description: "marginal nature is found in urban wastelands such as neglected creeks, wastewater treatment ponds, vacant lots, road and rail waysides, brownfields, fencerows, dumps, and alleyways. What emerges in this wastespace is the unintended product of human activity and nature's unflagging expressiveness, which I call Marginal Nature." Kevin M. Anderson is a geographer and philosopher who is the coordinator of the AWU - Center for Environmental Research in Austin, Texas. Check out his blog at http://marginalnature.blogspot.com/

Book Review: Drosscape by Alan Berger

Author Alan Berger, professor of urban design at MIT, takes an in-depth look at the leftover pieces of land in urban centers. Borrowed from Lars Lerup’s essay entitled “Stim & Dross,” dross refers to waste landscapes, the leftovers between developed lands. Berger calls this the in-between’s of a city’s urban fabric. He makes the case that urban lands are in constant flux and that urban sprawl is rampant, and will continue to do so even with the best of urban planning intentions. As business move out of the developed cores, obsolete lands form in the center, which spreads outward like a cancer. Lerup proposes that urban areas could intentionally provide a mix of developed and leftover lands, a hybridization of use and non-use. This is a refreshing concept and flies in the face of current urban planning, which seeks to place priority on infilling vacant lands (brownfields and greyfields) for new development. The idea is that infill curbs sprawl and perhaps maintain more forests and fields at the city edges. One problem with this idea is that unless there is an urban growth boundary (such as found in Portland, OR), infill doesn’t seem to hinder eventual sprawl. Something will build there eventually. The other, more insidious aspect, is that with an attitude of continual infill, few open green spaces are left within the city. Albert Pope, professor of architecture at Rice University, argues against filling in these voids. Continual infill results in communities like Roseville, Michigan; the city of my childhood that had no parks or open areas (other than athletic fields) within walking or biking distance—just wall to wall hardscape. Of course now with the demise of Detroit, the industrial edges of the city are becoming forested once again. Hopefully they will keep a few of these before they renew, redevelop, and infill. Berger takes a look at 10 urbanized areas in the book, ranging from Atlanta to Phoenix, and reveals the drosscapes found there, both in map form and aerial photos. Drosscapes presents a graphically intriguing overview of leftover lands in cities within an urban planning context. It provides some new terms for places that have no words—such as “demalling” (obsolete shopping mall areas) and “terrain vague” (economically failing areas). It also looks at cities at the metascale, providing a big picture view. But it also offers incentive to the architect, designer, or landscape architect at the project scale, to design “empty areas” within the property footprint—whether these be forested or reclaimed lands that remain unbuilt, or unpurposeful. What could these look like?

Wildlife Types Vary According to Urban Density

Cities tend to have similar wildlife types and habitats, no matter where you may live in the world. That’s why Norway rats, cockroaches, and pigeons are everywhere—they follow in our footsteps. But research has shown that native plants and wildlife are plentiful at the city edges but decrease as they get closer to downtown. Michael McKinney from the University of Tennessee sums this up nicely in his 2006 article in the journal of Biological Conservation. Entitled Urbanization as a major cause of biotic homogenization, McKinney collects a wealth of data from around the world, as well as mining existing data sets, on how wildlife and plants respond to urban density. He observes that cities tend to share similar wildlife types and habitat structures and thus are very homogenized (similar) and homeostatic (unchanging). Whereas city edges that abut natural conditions tend to be more varied and dynamic thus providing more habitat types and food for urbanophobes (wildlife that do not like being around humans and their environments). Based on the information and references McKinney provides in his article, I observed that there are three primary and distinct urban habitat zones—periurban, suburban, and urban. Or, in other words, the farther that one gets from the wildland interface and the denser the development, that wildlife and habitats change. This may be useful information to landscape architects or planners that seek to provide green spaces for wildlife habitat in densely urban areas.  The types of wildlife that you hope to attract probably depends upon the scale of habitat that you are designing and how they will arrive from native populations. The following graphic that I developed summarizes the general wildlife and habitat characteristics as provided by McKinney (2006):

It’s been noted that urban areas may exhibit a high diversity of plants and animals, sometimes more than the adjoining countryside. But while the numbers may be high due to more planted exotic vegetation species; the quality of the habitats, food, and ecosystem services may actually be more impoverished as compared to a native landscape. This is mostly due to the use of plants (native or exotic) with a reduced gene pool and a lack of resilience. McKinney notes that using local native plant species in urban areas enriches not only the urban genepool, but creates a much richer environment for people.

Somewhere in Starkville

Melbourne, Australia: The City Within a Forest

The “City of Melbourne is driving an ecosystem-based climate adaptation program with a goal to double urban forest canopy cover and increase permeability to cool the city’s summertime temperatures by 4°C. This presentation video reflects on how the City of Melbourne is implementing a transformative program of works to create climate resilient urban landscapes that support healthy ecosystems and healthy communities. In particular, it focuses on the role of citizen participation and transparency in co-designing plans to turn the world’s most liveable city into a city within a forest.” Learn more about this project in a video presentation by Yvonne Lynch, City of Melbourne Urban Ecology and Forest team, at the Biophilic Cities Project Youtube channel at https://www.youtube.com/watch?v=W6tpNXXUmow  (40 minutes).

More parks and green spaces in urban areas equals more bird species

 Northern flicker

A 2003 study published in Conservation Ecology has determined that more bird species are found in urban areas with parks and natural features than in more densely developed areas. The study by Melles, Glenn and Martin collected data at 285 stations in Vancouver and Burnaby, British Columbia, Canada. The authors counted the number of bird species present and noted the types of land uses around their sampling sites. In particular, they found that certain landscape features such as freshwater streams, large trees, and berry producing shrubs were correlated with the number of bird species. They conclude that parks and green areas should be integrated into city planning and development to enhance bird diversity. Housing developments adjacent green reserves should “minimize impervious surface cover (concrete, roofs and asphalt), minimize house size, maintain native tree cover and berry shrubs, integrate new ponds, and maintain and develop natural freshwater sources into planning designs.”

How old is your landscape?

 

Youthful landscape

Is it better to manage your landscape as an older woodland model or as a younger and youthful grassland? It depends. The context of what the property has on it and what is around it are important factors. But if it is biodiversity that you are after, then periodic disturbances might be your answer. Something called the “intermediate disturbance hypothesis” by Connell (1978) states that heavily impacted landscapes (regularly mown or burned) and undisturbed landscapes (older mature forest) results in less species richness. 

 

Medium aged forest

But those in-between aged forests, not too young and not too old (“overmature”), tends to have the most species present. This has been documented for birds (Jokimaki and Suhonen 1993) and butterflies (Blair and Launer 1997), but obviously this is not the case for all animal types. So to increase biodiversity on your property it may be advantageous to reduce the amount of lawn and convert it to woodland plants, while in a heavily wooded landscape it may be useful to thin the canopy branches or remove a few trees to open it to more sunlight. But then again, it depends.

Older woodland

49 Farms, San Francisco

I first saw Jay 'Blue Tape' Rosenberg a few years ago at Hayes Valley Farm in San Francisco. This urban permaculture garden had fat green squash plants interspersed with fava beans, marigolds, and rampant tomatoes. The garden was built upon the rubble of an abandoned interstate exit and yet it thrived with plants. 

 Jay Rosenberg

It began in layers with volunteers laying down thick sheets of cardboard to kill weeds, and then adding a mountain of horse manure and mulch. Within a few short years, the compost became black gold. Jay explained that he wasn't growing the plants to sell, but instead to give away-- to the volunteers and local folks who needed fresh food. It was a great success, and urban permaculture gardens took hold in the City by the Bay. 

Hayes Valley Farm was decommissioned by the City of San Francisco a few years ago, but it provided the seeds for starting other permaculture gardens in other neighborhoods. Now known as 49 Farms, their goal is to have a public permaculture garden for every square mile of the city. And it works. Find out more about 49 Farms and their good work at their website at https://sites.google.com/site/49farms/home

SURE-- Society for Urban Ecology

 Mission Statement

“In order to develop an understanding of the structure and function of urban ecosystems and to advance a balanced interaction between humans and their environments in cities and towns worldwide, the Society for Urban Ecology (SURE) exists to foster and develop knowledge and implementation of urban ecology worldwide by strengthening contacts and enriching the dialogue between researchers and practitioners, by representing the interests of the academic community within the wider international institutional context and by making the collective expertise of SURE available, where appropriate, in furthering the discussion of urban ecological issues.”

Find out more about Society for Urban Ecology at their website at http://www.society-urban-ecology.org/

 

 

Just what is Biodiversity, anyway?

More....of everything. Biologists define biodiversity as a richness of species, genes, and landscape types (Noss and Cooperrider 1994, Takacs 1996, Stein et. al. 2000). Lydia Schultz, a birder friend of mine from the Mississippi Gulf Coast, fully applies this concept to her 1/3 acre house lot.

 Zero Diversity

Schultz says that in order to attract more bird species to your property, simply plant more.....of everything. And arrange these into diverse groupings--grassy areas, aquatic zones, woodland types--even if these are no larger than 100 square feet each. And of course, the bigger the better.

Some Diversity

Creating your backyard habitat can be very easy once you understand that wildlife have three basic needs. These needs, food, water, and cover, promote use and provide the lifecycle needs of wildlife. 

FOOD—planting a variety of native trees, shrubs, grasses, and flowering plants that provide nuts, seeds, nectar, fruit, and other sources of nourishment. Providing food through natural vegetation is preferred. It tends to encourage the “natural feeding mechanism” that wildlife use.

WATER – Providing water for both drinking and bathing is vital to wildlife. You can include it by having birdbaths, drippers, or small ponds.

SHELTER/REPRODUCTIVE AREAS (space) – Nesting and shelter areas where wildlife are protected from the weather and predators is essential. Various species require different landscape features for these needs. Providing a diversity of plant material that includes evergreen and deciduous trees, vines, shrubs, herbaceous plants, grasses, and ground covers lets wildlife select the right areas for their feeding, nesting, and shelter needs.





Very biodiverse



Dr. Aldo Leopold, the “father of wildlife management,” said, “Habitat is like spokes in a wheel….” By removing one or more spokes you virtually weaken its stability. To make a habitat more sustainable try to visualize replacing the “spokes” that may be missing. For more information on how to increase biodiversity on your property, see Establishing a Backyard Wildlife Habitat pdf available online from MSUCares at http://msucares.com/pubs/publications/p2402.pdf



Urban Parks Home to Biodiverse Soil Microbes

We all know that there are many social, environmental, and economic benefits to preserving green spaces within the city. But we are still learning how important these benefits are, in some cases, many years after these parks were initially established. In 1853, the state legislature of New York voted to purchase over 700 acres of land in central Manhattan. Then occupied with swamps and rocky outcroppings, this land would become one of the nation's first landscaped public spaces in the United States--now known as Central Park. Back then, New Yorkers just wanted a public space to ride their carriages and have an alternative activity to sitting with their family in a tavern. Today, Central Park has a variety of outdoor activities and is the most visited urban park in the nation. It also offers a wealthy array of urban diversity with  nearly 400 plant species and around 350 animal species. Kelly Ramirez, Netherlands Institute of  Ecology, did her postdoc work on the soil microbes of Central Park in 2014. She sampled nearly 600 soil locations, and compared the life found within these to other soil samples taken across the globe. According to her team, they found 122,081 bacterial, 1659 archaeal, and 43,429 eukaryotic phylotypes (phylotypes are single-celled organisms that are difficult to identify). This stunning amount of soil biodiversity was unexpected, and shows that this urban oasis is on par with tropical regions, the Arctic, and the desert. In their paper published in the Proceedings of the Royal Society B, the authors state that most of the phylotypes were previously undescribed, and only 16.2 % of their genetic sequences showed in the Greengene database. They stated in their paper (2014) that "the broad range of cover types and management practices (fertilizer, compost, mulching, irrigation) within the Park allowed us to examine the factors structuring soil communities across environmental gradients while holding climatic conditions nearly constant." So the diverse areas of the park that includes wetlands, woodlands and managed garden spaces creates a diverse soil biota. The case for urban biodiversity may very well be found under our own feet.

The Battle of Maldon and other Old English Poems

"Wonderful is this wall of stone,
wrecked by fate,
The city buildings crumble,
the bold words of the giants decay.
Roofs have caved in, towers collapsed,
Barred gates have gone,
gateways have gaping mouths,
Hoarfrost clings to the mortar."
--unknown, quoted in Mitchell's The Archeology of Anglo-Saxon England