WHAT SHOULD I PLANT?

Jens Jensen, an early practitioner of the use of native plants and prairie restoration was influential at the turn of the 19^th century –his perspective promoted reconnecting people to their landscape in the face of rapid modernization and homogenization.

As early as 1924 The Garden Club of America published a booklet by Edith Roberts and Margaret Shaw on the Ecology of Plants Native to Duchess County, which led to the publishing of their book American Plants for American Gardens. This was one of the first books to promote the use of plant ecology and native plants in gardening and landscaping.  According to Darrel Morrison, (former Dean + Professor emeritus at the University of Georgia) who wrote the introduction to the reprinted copy in 1996,  “utilizing patterns and processes that are intrinsic to naturally evolved landscapes, we can create designed and managed landscape that are clearly “of the place” and approach the ideal of sustainability.” We can also “protect biological diversity in the human developed landscape”.

Equally influential in this discussion was Ian McHarg’s, Design with Nature, the seminal text written in 1969 and consistently reprinted every decade since.  It stressed the importance of considering ecological and environmental factors. According to Time Magazine, which labeled him “ an apostle of using ecology for planning”,  he “cries that man is poisoning the very biosphere that sustains him and calls for a new ecological religion based on living in harmony with nature rather than on conquering it.

Janet Marinelli of NYBG writes that “biologists consider invasive species to be one of the two greatest threats to native plants and animals, second only to the outright loss of habitat to suburban sprawl, agriculture and industrial development.”

Within the last ten years the argument for planting natives over exotics has become heated.  Virtually every garden magazine writes on natives, garden shows promote it and design competitions award methods of sustainability, inclusive of which is planting natives.

Currently, academics such as Doug Tallamy (Professor and Chair, Department of Entomology and Ecology, University of Delaware) write and lecture about the link between insects and native plants. In his most recent book “Bringing Nature Home” he exclaims that as biodiversity depends upon native plants, invasive turfgrass lawns limit the “carrying capacity” – that is the amount of species and foods available in a healthy ecosystem. The challenge is to recreate foodwebs in our gardens as some plants (natives) are significantly more effective that non-natives.

For millions of years these native plants have co-evolved with the native insects, and most insects can only reproduce and feed on the plants that they share an evolutionary history with. Wildlife is threatened when suburban development encroaches on once wild lands. As these beneficial insects are deprived of essential food resources when suburban gardeners exclusively utilize nonnative plant material. This leads to a weakened food chain that will no longer be able to support birds and other animal life.  As we’ve lost 40% of all bird life in the Northeast over the last fifty years, this presents a compelling argument.

** It is important to note that native is not necessarily of the same country or continent, rather part of the same plant community or the same evolutionary background.  Interestingly, a plant that is moved outside of its “native range” can still perform similar functions within this new ecosystem if it is linked genetically to a relative that typically exists within that new ecosystem. “Animals adapted to using/eating one member of a genus are often able to use a ‘congener’, (a member of the same genus) even if they have never interacted with that particular plant species in their evolutionary past.  Traits such as leaf chemistry, shape, toughness can be so similar among cogeners that adaptations enabling an insect to grow and reproduce on one member of the genus predispose that insect to using other members of the genus.” 1

An example below...

 Rhododendron periclymenoides (Pink Azalea)

photo: ctbotanicalsociety.org

Rhododendron viscosum (Swamp Azalea)

photo: plantsmen.com

Tallamy urges readers to do what they can to eliminate invasive alien species, to use native plants, to replace sterile lawns, which consist of two or three alien grass species that support little more than Japanese beetle grubs, with sustaining native plant refuges.

“There is no redundancy in plant species here, and consequently no redundancy in the community of natural enemies that can survive in lawn based habitats. There is no hope of controlling the millions of Japanese beetles being produced in our neighborhood lawns each year.  The balance to control Japanese beetles can be achieved through well designed landscapes founded on a diverse array of native plants.” “Planting one type of crop typically favors only a few types of insect herbivores – not enough to support a diverse, redundant community of predators and parasites.  Under these oversimplified conditions, herbivorous insect populations typically escape the control of their natural enemies and explode.   This is good for the pesticide industry but little else.” 2

He urges those who live in suburbia to plant native shade trees, possibly groves, to plant natives along lot lines to begin reestablishing productive areas where insects can successfully reproduce and live, and where their predators can find security and cover.

1 Doug Tallamy, Bringing Nature Home

2. Ibid, D. Tallamy

WHAT DO I PLANT?

Should I plant native, exotic or spontaneous plant material?

Invasive plants are introduced species that can thrive in areas beyond their natural range of dispersal. These plants are characteristically adaptable, aggressive, and have a high reproductive capacity. Their vigor combined with a lack of natural enemies often leads to outbreak populations into our nations' fields, pastures, forests, wetlands and waterways, natural areas, and right-of-ways. Variously referred to as exotic, nonnative, alien, noxious, or non-indigenous weeds, invasive plants impact native plant and animal communities by displacing native vegetation and disrupting habitats as they become established and spread over time. Most people consider an invasive species to be one that was NOT here prior to the settlements of Europeans in North America. The U.S. Government defines it as one that is "not native to the ecosystem under consideration and whose introduction causes or is likely to cause economic or environmental harm of environmental harm or harm to human health.”

To the home gardener and landscape designer the question is “what do I plant?” This a challenging question to many. For example, the Multiflora Rose (Rosa multiflora) is beautiful, as is Chinese Wisteria (Wisteria sinensis).  English Ivy (Hedera helix) is evergreen and  an immediate "catch-all" answer to climb walls and provide groundcover.  A Norway Maple (Acer platinoides) and Tree of Heaven (Alanthus altissima) are lovely shade trees, brought to this country after several blights virtually eliminated other species,...but now they has been outlawed to plant in most states.  Many people would rather have an invasive that survives regardless of the soil type; irrigation and care provided them, not to mention the fact that to some extent they are exempt from most insect damage.

There’s appears to be an evolving and multi-layered discussion/debate among academia on what plants that we as caretakers of the planet and home gardeners should plant.  For years we have planted in the United States exotic species following in the steps of the English, for whom plant collection, gardening and horticulture is a national religion or obsession (dependent on who one speaks to), influenced by nursery catalogs, books and television shows. In the next few blog posts I aim to explore this subject.  I see this as more than a simple question of personal choice but one that has far reaching ramifications with integral ethical and moral dilemmas.

LABYRINTH

The Labyrinth is an extension of man's desire to co-create with nature. Labyrinths are known as sacred gateways which have been found at the entrance of ancient sites around the world. Ancient historians such as Herodotus and Pliny the Elder spoke of grand labyrinths attached to burial sites of rulers (such as “Hawara” built for Amenemhat III, (about 1855-1808 BC) near present day Cairo. 

 illustration: A Virtual Exploration of the Lost Labyrinth

A labyrinth has only one path leading to the center and back out again. There are no dead-ends or trick turns which one encounters in a maze.  A distinct difference between the two.

The spiral is the most generative form of subtle energy. When its coil is unwound the stored energy is released. The areas where straight ley lines cross, or where underground water run are places to build sacred temples, labyrinths. When you walk a labyrinth, you meander back and forth, turning 180 degrees each time you enter a different circuit. As you shift your direction you also shift your awareness from right brain to left-brain. This is one of the reasons the labyrinth can induce receptive states of consciousness. These places are rich in both yin and yang (yin underground water crossing yang energy lines). The labyrinth resonates to this numinous spiral, the Phi ratio known as the 'Golden Mean' found in all of nature. Perhaps this also bears a suggestion to the axis mundi of a site—another cosmic centering device which takes into consideration an awareness of the three vertical strata: above, below and a terrestrial middle plane – suggestive of heaven, earth and the underworld.  

photo Wikimedia Commons

Noted historian Elizabeth Barlow Rogers writes - “People have sought at certain times and places a correspondence between abstract, philosophical notions of space and designed manifestations of space.  The builders of the cities of Ur, Knossos and Teotihuacán centered their constructions in landscape space according to a cosmological diagram. At Vaux-le-Vicomte and Versailles there is a firm relationship between Cartesian cosmology and experiential space.” 

In medieval and earlier times these were created as a religious path toward salvation or enlightenment.  “Le chemin du paradis” literally means the road to paradise -- a pilgrimage.  And so it is written at the Labyrinth of the Cathedral of Chartres.

This desire for a correspondence between philosophical and scientific concepts of space and landscape can be seen in present day. Modern labyrinths, those created in the present are typically used to create a contemplative state such as the 9/11 labyrinth memorials at the Battery in NYC and at Boston College (below). 

 Boston College Labyrinth.  photo Wikimedia Commons

Two weeks ago I wrote of landscape design and land art in Ireland.  Perhaps images within that book inspired this post.

photo by Allan Pollok-Morris

COURTYARD

One of my favorite texts, “A Pattern Language” begins its discussion of courtyards critical of the many courtyards built in modern buildings which are very often considered “dead” space."  “They are intended to be private open spaces for people to use – but they end up unused, full of gravel and abstract sculptures.” 

Reasons for their failure according to the authors are three-fold. 1) The connection between indoor and outdoor space and the transition between the two is not sufficiently addressed – “people need an ambiguous in-between realm – a porch or a veranda, which they naturally pass onto often, so that they can naturally drift to the outside.” 2) The space lacks functionality and circulation – doors should be on opposite sides, “the space “becomes a meeting point for different activities, provide access to them, overflow from them and cross-circulation” between these doors/portals. 3) There are no “loopholes” – or views beyond the space --- you should not feel completely enclosed within the courtyard.

 Bodleian Library (first image) and Courtyard (latter two images)

I agree whole-heartedly with the authors, but in deference to them, these “design failures” of courtyards do not always limit them.  Recently I visited the courtyard of the Bodleian Library at Oxford University, a four hundred year old space (originally built in the early 1600’s) and considered these design precepts as I meandered through it’s courtyard.   What do you think?

For a 360-degree view of the courtyard which provides a unique perspective as if one were actually there, try this link: Panoramic photograph of Bodleian Library Courtyard, Oxford

Ironically the publisher (of this text) was Oxford University Press! As another aside, The Library's fine architecture has made it a favorite location for filmmakers.  The Bodelian Library can be seen in the first two Harry Potter films.


*all quotations from A Pattern Language: Towns, Buildings, Construction by Christopher Murray/Sara Ishikawa/Murray Siverstein
New York: Oxford University Press  1977
**unless noted, photograph of Bodleian Library Courtyard ©Todd Haiman 2010