Human Flower Project

Science

Friday, May 09, 2008

Warm the Cacti, Cool the Computers

An Indiana city saves on heating, while the university pays less to chill its super computers. Kiss your brain!

Computer scientist 
Paul Brenner of Notre Dame explains how the university’s computers and the city’s desert plants will make beautiful climate together.
Photo: University of Notre Dame

Better than a stroke of genius, here’s a spike of conservation brilliance.

The University of Notre Dame’s computer experts have teamed up with botanists of South Bend, Indiana, to save energy. They’re moving several of the university’s 400-pound computer processors into the city’s Arizona Desert Dome.

The computers shed heat, which is just dandy with the cacti and other Southwestern plants, and air circulating through the 26,000-square-foot greenhouse will help cool the machines. Big computers like these are very expensive to keep cool. “According to The South Bend Tribune, the plan will save the university about $100,000 in utility costs, even after the university pays for the electricity to power the processors.” Nobody knows yet how much the computers’ warmth will save the city, but last year South Bend’s parks department spent $70,000 to heat the desert dome and other conservatories.

According to Kathleen, a South Bend blogger and conservationist, this region of Indiana “relies heavily on coal-powered generators for electricity,” so this Desert Dome/Computer partnership should reduce emissions from burning coal, heating the desert greenhouse while cutting down on greenhouse gases.

This forward-thinking human flower project grew out of the city of South Bend’s commitment to climate protection. Last month, South Bend became one of 800 Cool Cities dedicated to reducing the causes of global warming.

With amaryllis looking on inside the Potawatomi Park Greenhouse, Mayor Stephen Luecke (right) is honored by Christine Fiordalis and Steve Francis of the Sierra Club. South Bend became a “Cool City.”
Photo: Kathleen, If We Only Connect

“This Green computing initiative proves that global challenges can bring out the best of our creativity,” said Mayor Stephen Luecke, “especially when the public and private sector join together to find solutions. It is only the latest of a history of ventures by the City of South Bend to reduce our carbon footprint and make a real difference for the future of our planet.”

Couldn’t such a climate partnership work between any botanical garden (or private business) with greenhouses to heat and any company or institution with computers to keep cool? Congratulations to scientists of Notre Dame and the city of South Bend. May your initiative spike others into collaboration.

Friday, April 25, 2008

A Tall Order—Large Stature Trees

What lengths would you go to for shade, good drainage, and year ‘round beauty? Urban arborist Georgia Silvera Seamans explains the benefits of tall trees and ways to plant these giants successfully in cities. Thank you, Georgia.

Cycle path, Lincoln Parkway, Buffalo
Source: Heartland

By Georgia Silvera Seamans

The “Right Tree in the Right Place” (RTRP) concept encourages municipalities, NGOs, and homeowners to plant trees shorter than 25 feet under overhead utility lines. The crowns of large stature trees, encroaching on wires, can cause a number of problems: downed branches that interrupt utility service, tree trimmers’ perilous contact with live wires, and the conventional pruning of tree crowns into U-shapes (these tend to be structurally unsound and are nearly always unattractive).

Consequently, following RTRP along roads and in neighborhoods with overhead wires yields a short canopy. Redbud, purpleleaf plum, crape myrtle, “flowering” cherry, crabapple, Japanese lilac, and trident and hedge maples, these small stature trees both look and function differently than do streetscapes of large trees like elm, London plane tree, sweet gum, tulip tree, ginkgo, oak, and linden.

Let’s consider some of those differences.

Setback trees on private property create sidewalk shade.  Berkeley, CA.
Photo: Georgia Silvera Seamans

The aesthetic contribution of short stature trees tends to be limited to their flowering season, while the arching canopy effect of larger stature trees is a year-round feature. Also, short canopies, while beneficial to wildlife, produce smaller ecosystem benefits.  (See “Street Trees: Let’s Think Outside the Wires.” Short stature trees have tremendous habitat and food value.  Take urban birds.  They utilize different layers of the urban forest canopy. As Julie Zickefoose writes in Natural Gardening for Birds, short stature hawthorns provide berries, while larger stature ashes and locusts provide nesting.)

Here are other benefits provided by larger stature trees:

• They provide more shade for infrastructure like streets: “shade on the street segment with large-stature trees will reduce costs for repaving by $2,900 (58%) over the 30-year period compared to the unshaded street. Shade from the small-stature trees is projected to save only $829 (17%)” (From Why Shade Streets? by the Center for Urban Forest Research, 2006).

• In terms of air pollution, “the annual net reductions for pollutants range from 10.1 lbs for a 40-year-old large tree to 0.7 lbs for a 40-year-old small tree. And values range from $64 for a 40-year-old large tree to $1.62 for a 40-year-old small tree” (Center for Urban Forest Research, newsletter, January 2005).

To learn more, here are three good resources (al pdf files): the CUFR’s 2003 newsletter “The case for the large tree”; 2001 Factsheet #1 about the benefits of large front yard trees; and Dr. Greg McPherson’s 2003 article, “A benefit–cost analysis of ten street tree species in Modesto, California, U.S.,” published in the Journal of Arboriculture.

Another deficit of the Right Tree for the Right Place formulation is its ignorance of design factors.  Street trees are typically planted at the street edge of the sidewalk.  Wires are generally sited towards the edge of the sidewalk, too.  With this inevitable conflict for over space, streets with overhead wires are usually planted with short stature trees.  But, street trees could be planted on the building side of the sidewalk or in front yards (preferably through an easement so that the city has some oversight about removals).  There are actually several such “setback” programs in the U.S.  The City of Boston Parks Department sponsors one, (and is enabled to do so according to Massachusetts General Law).  Public trees can be planted on private property as long as they are within 15 feet of the public right of way.  EarthWorks Projects in Boston, MA, initiated the Setback Trees Project in 2007, self-described as planting “trees on private property for the common good.”

Bumpout (note this bumpout is not connected to the sidewalk) – tree is just outside overhead wires.  Berkeley, CA
Photo: Georgia Silvera Seamans

There are other design possibilities.  Trees could be planted in bump-outs located beyond overhead wires, in traffic circles at neighborhood intersections, or in the center of neighborhood blocks (see photo below).  (Traffic calming is one co-benefit of planting trees in the center of the roadway or at an intersection.)

And overhead wires could be buried.  This is an expensive proposition; according to The Seattle Times, the cost to the city of burying utility wires for a local project was $350-$400 per linear foot.  In another Washington community, the cost of burying electric, phone, and cable wires was estimated at $2500 per foot.

However, tall urban street canopies provide considerable benefits long-term.  The conflict between large stature trees and overhead wires is not new.  In his fascinating book, Republic of Shade, about the American elm (Ulmus americana) in New England, Thomas J. Campanella describes anti-elm sentiments expressed in an 1853 article from the New York Times:

“Most American cities were in urgent need of a pruning.  Larger, ‘weedy’ species should be removed at once, (the Times writer) argued, and replaced with smaller trees ‘of a character that can be trained around the wires.’ Elms, very big and very weedy, must be sacrificed to appease the goddess of electricity.”

Appeasing the gods of electricity: large trees pruned into u’s under wires on Old Brownsboro Road, Louisville, KY
Photo: Human Flower Project

Campanella also notes that changes in road technology affected trees.  Street surfaces before 1890 did not restrict “the passage of water, nutrients, or oxygen to the roots of adjacent trees,” but asphalt and concrete paving “virtually sealed the surface of the street,” depriving trees of all three. 

Another dimension of “Right Tree in the Right Place” is to select species according to the size of the growing area—most often the square foot of the sidewalk cutout or width of the tree lawn (the grass strip located within the sidewalk).  This is a very reasonable concept.  Healthy trees depend on adequate root systems, which requires sufficient area to grow.  Often, according to landscape architect and arborist James Urban, we look up at tree crowns and ignore what’s happening below ground.

Different cities have different standards.  In the City of Boston, the minimum tree well area is 24 square feet, often a 3x8 foot or 4x6 foot sidewalk cutout.  One East Bay, California city’s minimum standard is 2x2 feet or 4 square feet!  Generally speaking, a foot of root area supports an inch of trunk diameter.  Accordingly, at only four inches in diameter at breast height, a tree with a well area of 4 square feet has maximized the initial growing area for its root system.  This tree will seek additional space either within the sidewalk (made visible by buckling) or in someone’s front yard.

A small cutout clearly will restrict the size of the tree that can be planted initially.  For example, a 2x2 foot area cannot adequately accommodate a tree that is two inches in diameter whose root ball is two feet in diameter.  On average, for every diameter inch at planting, a tree needs a year to establish.  So, a two inch tree will take two years to establish.  Although, a 15-gallon tree (the size frequently planted in a 2x2 foot cutout) will establish faster, its aesthetic and functional presence is less significant than a larger diameter tree.

The 2x2 foot area is the minimum, so presumably a larger growing area will be provided if the sidewalk can accommodate it.  Although a 3x8 or 4x6 space is significantly larger, it can only support a 24-inch diameter tree within the original cutout.  Ideally, street trees would be given larger growing areas for their root systems.  However, if the sidewalk is space constrained (Americans with Disabilities law requires four feet of clearance for accessibility), what are the options? 

Annie’s Oak, Berkeley, CA
Photo: Georgia Silvera Seamans

One option is to install structural soil beneath the sidewalk.  Structural soil is an engineered medium that supports root growth while simultaneously satisfying engineering load-bearing requirements.  The most well known structural soil recipe was developed by Cornell University’s Urban Horticulture Institute.  An older version of structural soil is sand-based, also known as Amsterdam structural soil.  The most significant difference is that CU soils can achieve a greater level of compaction (important for load bearing) and still sustain root systems than can the Amsterdam soil – 95% versus 85-90%.  The installation of structural soils could be undertaken as sidewalks are repaired, redone, or created.  Like the burying of overhead utility wires, this solution is costly, but again, the potential benefits to a city, its trees, streets and people are significant. 

Thursday, April 10, 2008

Street Trees: Let’s Think Outside the Wires

Local Ecology’s Georgia Silvera Seamans explains why, in choosing a city’s trees, there’s a lot more to consider than power lines.

Hawthorn tree in bloom: short, showy, and nectar rich
So why isn’t it a choice of Oakland’s city foresters?
Photo: Georgia Silvera Seamans

In urban settings, human tensions arise over the selection of large stature or small stature street trees.  The “Right Tree in the Right Place” planting policy recommends that short stature trees – 25 feet or less – should be planted beneath utility lines because the canopies of these trees do not interfere with overhead wires.  But emphasis on height alone neglects larger issues—of ecosystem value. 

Large stature trees—like red oak, London plane tree, or sweetgum—do interfere with overhead wires, but they also provide greater ecosystem benefits than do small stature trees: they sequester (store) more carbon, filter more particulate matter from the air, and intercept more rainfall via leaves, trunk, and soil (and slow runoff into storm drains). And, because of their larger crown spread and evapotranspiration capacity, larger trees cool larger areas of surrounding air (cooling nearby infrastructure and buildings, too).

In a study of Berkeley’s street tree canopy conducted by the USDA Forest Service Center for Urban Forest Research (CUFR), researchers found that city trees saved $12.58 per tree in annual electricity costs. As for capturing stormwater runoff, the average street tree intercepted 1,478 gallons, a value of $5.91 per tree annually. The researchers also found that, overall, larger stature trees provided the most benefits: the average small, medium, and large deciduous street tree produced annual benefits totaling $32, $79, and $96, respectively. (Note: Author Georgia Silvera Seamans, assisted by Qingfu Xiao, research scientist at UC Davis, obtained this information as part of a research grant with Urban Releaf.)

Ginkgo (Ginkgo biloba): as with many large trees, its flowers aren’t showy
Photo: Georgia Silvera Seamans

Though not all short stature trees have showy floral displays, they tend to have larger, more conspicuous flowers. Most people think of herbaceous perennials as the plants that attract bees and butterflies, but flowering trees are definitely popular with wildlife too. As cities make tree selections, they should consider the “wildlife-value” of species that produce fruits, seeds, nuts, catkins, and acorns.  A tree’s wildlife-value in the larger ecosystem, something not usually quantified, involves its floral services for small, highly mobile species like butterflies and bees and some birds.  Hummingbirds, for example, utilize showy flowers for nectar.  As well, floral displays attract insects on which non-nectar eating birds rely.  Not only are the showy flowers of shorter stature trees attractive to birds and bees, their exuberant flowering draws “oohs” and “aahs” from us humans.  I have never visited Washington, D.C., in the spring, but I have heard the buzz about the mass blossoming of the Mall’s 3,000 cherries.  (At this year’s San Francisco Flower & Garden Show, the USDA Forest Service created an urban forest garden.  The sign below the coast live oak, interestingly enough, listed the aesthetic monetary value of the oak over 40 years as $5,210.)

Given the dual appeal of short stature trees, I was curious to see which varieties municipal urban forestry departments selected.  A natural choice for a case was the City of Oakland.  I am an intern of urban forestry issues for the City of Oakland Mayor’s Office.  Oakland’s street trees are managed by its public works agency.  The city’s Official Tree Species List, as of November 2007, has a limited palette of small stature trees.  The list contains seven species: Strawberry tree (Arbutus unedo), Eastern redbud (Cercis canadensis), Crape myrtle (Lagerstroemia indica), Photinia (Photinia fraseri), purple leaf plum (Prunus cerasifera ‘Thundercloud’), Evergreen pear (Pyrus kawakamii), African sumac (Rhus lancea), and Water gum (Tristania laurina ‘Elegant’).  Many of Oakland’s residential streets are lined with overhead utility wires, so I expected a longer list of short stature trees.

Of these seven species on Oakland’s approved street tree species list, four have documented wildlife value.  According to the USDA Forest Service Silvics Manual of North America (1990), the eastern redbud nectar is used for honey production (and the fruit is eaten by cardinals, bobwhites, ring-necked pheasants, rose-breasted grosbeaks, white-tailed deer, and gray squirrels).  The crape myrtle attracts “beneficial insects” according to the UC Davis Arboretum plant database, but it does not give a list of insect species.  Water gum or Tristania laurina provides nectar to honey bees; these bees are common to very common visitors of the water gum flowers.  The UC Berkeley Urban Bee Garden project also observes that water gum flowers occasionally attracts small, native bees.

A powerline-centric view of urban tree selection
Image: Pacific Gas & Electric

As mentioned previously the primary limiting factors in planting the right tree in the right place with regards to overhead utility lines is height; trees should be twenty five feet or less in height at maturity.  Of the seven species listed by the City of Oakland as “small,” two can attain thirty feet in height: the crape myrtle and the purple leaf plum.  Two of the species categorized as “medium” are listed with heights of twenty feet: the bronze loquat (Eriobotrya deflexa) and the Saint Mary magnolia (Magnolia grandiflora ‘Saint Mary’).  In general, magnolias are medium-sized trees, but I gather that the Saint Mary variety is typically twenty feet at maturity.  The flower of the loquat attracts bees (and birds eat the summer fruit). 

The City of Oakland does not list the hawthorn.  I have noticed bees buzzing around and landing on hawthorn (Crataegus species) flowers in my Berkeley neighborhood.  My casual observation is supported by the UC Berkeley Bee Garden project.  Crataegus laevigata attracts five to nine honey bees every three minutes for pollen and nectar, while C. phaenopyrum (Washington hawthorn) attracts five to nine honey bees every three minutes and occasionally attracts small and medium bees for nectar.

Of course, wildlife value is not limited to short stature, showy, flowering trees, and flowers are not the only source of value.  Linden trees (Tilia species) attract bees in great numbers according to observations made by the Cornell University Arboretum.  The valley oak (Quercus lobata), according to the UC Davis Arboretum plant database, attracts butterflies, beneficial insects, and birds.  But, the valley oak does not make a good street tree.  Urban sidewalks are not designed to accommodate this large, broad-crowned California native that requires “deep soils where it can tap groundwater.”

A coast live oak in its namesake city, Oakland, California
Photo: Georgia Silvera Seamans, Local Ecology

Actually, the City of Oakland is named for the oaks that used to cover its land area.  The coast live oak (Quercus agrifolia) is conspicuously absent from the city’s list of large tree species.  This species would require a large growing area and the majority of residential sidewalks in Oakland are six feet wide; a four-foot right of way is required by the Americans with Disabilities Act.  To see an urban mature coast live oak (and its optimal growing space), visit Oakland’s City Hall Plaza.

Friday, April 04, 2008

Pollution Snuffs Floral Scents

New environmental research shows how bad air is very bad news for bees, moths, and the flowering plants they visit.

After a long search for flower scent, this bee is fed up
—but still hungry
Image: Simpson Trivia

Does your life depend on perfume?

Ours does, and, conveniently, we can order another bottle of Mitsouko as needed. But many bees, moths, and other insects must rely on scented flowers—for food.  The flowers they visit also depend on their own fragrances to reproduce, by drawing pollinators in.

A study by Quinn S. McFrederick, James C. Kathilankal, Jose D. Fuentes, published in Atmospheric Environment, shows that air pollution destroys the scent signals of flowers, an effect of bad air that makes pollinators less efficient and plant colonies less robust.

The scholars set up a model to trace how specific scent-producing hydrocarbons released from flowers react with major pollutants in the air: ozone, hydroxyl, and nitrate radicals. They looked at three particular hydrocarbons—linalool, b-myrcene, and b-ocimene—“known to be common scents released from flowers.” Introducing variables of wind and temperature, they examined how these “perfumes” would change as they encountered polluted air parcels. When the scent compounds react with the pollutants, they begin breaking down fast, becoming unrecognizable to pollinators (as when the ambergris disappeared from Dioressence).

Linalool, a common floral scent compound, breaking down as it reacts with ozone
Image: Courtesy Jose D. Fuentes et. al

The scholars, from University of Virginia’s Department of Environmental Science, write that this feature of air pollution has not previously been studied, though they note that earlier research had found another threat to plants. Floral hydrocarbons (fragrances) also attract natural enemies of herbivores; as airborne pollutants like ozone react with floral scents, the “natural enemies” do battle elsewhere and the herbivores have, as it were, a field day.

Charts showing how the range of floral fragrance compound linalool becomes smaller and smaller with increases in air pollution.
Image: Courtesy Jose D. Fuentes et. al

These charts, based on a Lagrangian model, show how dramatically interaction with air pollution limits the range of floral scents. The “scenario” at top left shows the dispersion of floral scent-compounds in a pre-industrial environment; the one at lower right shows what occurs in a highly polluted setting. The scientists write: “For highly reactive volatiles the maximum downwind distance from the source at which pollinators can detect the scents may have changed from kilometers during pre-industrial times to 200 meters during the more polluted conditions of present times.” Do you smell a problem?

Heads up, Judy Glattstein and other New Jerseyites! “These hydrocarbon–air pollution processes are likely operating in landscapes such as the eastern United States where summertime air pollution levels can become substantially higher than the ones observed in the rural atmosphere away from anthropogenic (a.k.a. human) influences.”

The scholars note that this impact of air pollution should be harshest on those plants that depend on “specialist pollinators,” since the chemical breakdown of floral hydrocarbons tends to blur fragrances, creating a generic “smell”:  “what was a unique signal in the 1800s has become a general signal.” They also look ahead to research that might compare the olfactory receptors of insects in polluted and non-polluted environments—looking for signs of evolution. A thought: How about comparing the fragrances emitted by patches of city and country larkspur? Might flower scents be evolving too?

Many thanks to Dr. Jose D. Fuentes for sending us the paper.

Tuesday, February 26, 2008

Project Budburst ~ Late to Science

On the lookout for flowers? This is our kind of science project.

Pink Primrose (Oenothera speciosa) in Austin, TX
nearly ready to report on climate change, 2/26/08
Photo: Human Flower Project

We’re not much for joining. We were always mediocre at science. But as of today we’re all aboard Project Budburst.

The University Corporation for Atmospheric Research—a group of 70 universities-- is trying to track climate change in the U.S. by engaging “citizen scientists” to report when plants leaf out, bud, and bloom. Has global warming changed the lives of lilacs, dandelions, or mayapples in our yards? Well, first we gotta look.

“Watch locally, discover globally” seems the motto of this effort. Compiling observations from people all across the nation, the scientists who dreamed this up can get a surer sense of how our planet is changing. “Plants can serve as quite sensitive climate sensors,” Dr. Kay Havens, a project leader and director of plant science and conservation at the Chicago Botanic Garden, told Steve Curwood.  “By looking at bloom time and leaf time that gives us a good indication of whether or not the temperature is changing in an area.”

Project Budburst makes reporting on local plants easy

Last year’s pilot study drew over 900 observations “and of those, nearly two thirds were done by children under 12,” Havens said. How often do you get to take part in a nationwide, multigenerational science project—no math skills required? They make it a cinch to register (either by name or anonymously), find your latitude and longitude, and then choose a tree, shrub, wildlflower or weed to keep an eye on. You can pick from their list or select a local plant that interests you.

We’ve selected Pink Primrose (Oenothera speciosa) as there’s a little patch of it right down by our curb (and Glenn Whitehead’s big pastel drawing of them on the wall inside; it blooms twelve months a year). As of today we see leaves but no buds in the yard. But three doors down, at Victor’s, it looks as if we may be able to report a bloom later today. (Any specimen within a half mile is in bounds.) This plant, we learn, blooms in the mornings in some parts of Texas, in the evenings elsewhere. so we’ll also discover whether the primroses hereabouts are larks or owls.

Project Budburst was launched two weeks ago, so we’re a bit late getting started. But there’s nobody handing out grades (or gold stars, for that matter). We hope that our U.S. readers will consider taking part in this far-sighted Human Flower Project and that readers in other parts of the world will let us know of more citizen-science efforts to study climate change.

Friday, February 08, 2008

Year of the Rat Pollinator

Bees and bats do it, as do mice—pollinate flowers, that is. Some of South Africa’s most marvelous low-to-the-ground species should have a banner year.

Paper cutout/Year of the Rat
Image: Hudson Museum

Happy New Year to all our Far Eastern readers, and anybody else who’s ready to start over…

Year of the Rat began February 7 and will extend through January 25 of next year. As usual, the stock market swamis are chiming in (though we haven’t yet seen a rodent festooned at Korea’s stock exchange, as an ox was in 2006).

But no matter what the dollar and yuan do, 2008 should be terrific for proteas and the succulent karoo. Both are therophilous plants, meaning they’re pollinated by rodents ("rats," if you like).

Namaqua Rock Mouse (Aethomys namaquensis) pollinating Protea humiflora
Photo: Colin Paterson Jones

This gorgeous photo, by Colin Paterson Jones, shows a Namaqua Rock Mouse pollinating Protea humiflora (protea is the national flower of South Africa). Not mice only, but shrews, gerbils, and—yes, rats—visit several of the low-to-the-ground species of proteas and Hook Pincushions.

“Rodents are attracted by a strong musty odour, and a reward of syrupy sugar which is secreted in large quantities. In order to prevent birds and insects from stealing this nectar, rodent-pollinated (therophilous) proteas have inconspicuous brown or black involucral bracts. Flower-heads are usually hidden inside the bush at ground level, where they are accessible to rodents. The insides of the involucral bracts may be pale white and the tips of the flowers may be shiny red - both serve to guide the rodent to the nectar in the dark.” Here’s much more about the experiments, photos, too.

Steven D. Johnson, a botanist at the University of Natal in Petermaritzburg, South Africa, set up a night experiment to discover the pollinators of the dramatic Massonia depressa, also known as Succulent Karoo: “Imagine water lily leaves spread on the ground,” says Johnson. He and his team released gerbils in an enclosed area around the plant “and the rodents dove for nectar, leaving the flower intact but their snouts gilded with pollen.”

Here’s more on Year of the Rat, including a description of rat-natives’ more and less appealing traits. For proteas and succulent karoo, the most vital of these is certainly industriousness. Get down!

Saturday, February 02, 2008

106 Million Players:  Super Turf ‘08

James Wandersee and Renee Clary give us the scoop on the Super Bowl’s portable field-in-a-pan. No matter which team wins, this history of athletic turf is unbeatable. EarthScholars, Rah!

Archimedes applying his (super) lever to the globe
Image: via Chris Rorres, Drexel University

By James H. Wandersee and Renee M. Clary
EarthScholars™ Research Group

Archimedes, the ancient Greek mathematician and inventor (280-211 BCE), once boasted, “Give me a place to stand and I will move the Earth.” He was, of course, talking about his levers as force multipliers and the amazing things they could do.

Surely Archimedes was exaggerating about moving the Earth, though.  No machine could ever do that.  Or, could it?

On February 3rd, 2008, the world’s television-viewing public will have a chance to see the first-ever Super Bowl to be played within a new kinetic architectural marvel—a stadium designed by Uni-Systems® to make the Earth literally move—at least a good chunk of it!

The new University of Phoenix Stadium in Glendale, Arizona, is a modern sports wonder, not only of stadium design, but also of horticulture and turf-grass science.

Given the stadium’s location in the warm Southwest, heat build-up, high humidity from the plants’ transpiration, and uneven sunlight reaching the field through the roof aperture would certainly limit the arena’s usefulness if Bermuda Grass and Ryegrass turf were grown inside this dome.  The stadium would also require supplemental incandescent lighting (as does the Bull’s Eye Bermuda Grass used in the Arizona Diamondbacks’ baseball-only-facility, Chase Field, in downtown Phoenix). But University of Phoenix Stadium is the first dome to have—along with a retractable roof and full air conditioning—a retractable 94,000 sq. ft., playing field of living grass!

The retractable field scoots on nearly 550 traction-drive wheels, riding upon 13 rails embedded in the concrete floor. Guide wheel assemblies on the center rail maintain the field’s alignment as it moves in and out. Seventy-six one horsepower motors drive the field through the stadium’s southside doors at a rate of about 11 feet per minute (1/8 mph).

CMX Sports Engineers designed the field to react like a traditional grass playing surface, so that players feel safe, comfortable, and confident, whether they are running, jumping, fielding, or tackling each other. At the throw of a switch, the 9,300-ton retractable grass playing field can be moved into the stadium for a football game. The 2.1-acre field relocates into or out of the stadium in approximately 1 hour.

The “Grass on a Pan” Growing Outside the Stadium
Photo: Uni-Systems

On non-game days the playing field rolls from the stadium on a 19-million-pound tray, residing outside where Arizona’s typical sunny conditions are ideal for maintaining grass. The immense pan-type “pot” has all components needed for healthy grass—irrigation, drainage, and an optimized growing medium. The grass grows on top of a foot of sand; under that is the irrigation plumbing, and beneath that plumbing is the tray liner that prevents the water for the field from leaking onto the wheels and power train. Archimedes would surely be impressed!

This “grass on wheels” design provides an attractive space for non-football event planners. The field moves on steel rails that sit nearly flush with the facility’s floor, a low-profile with the grass surface a mere 42 inches above the concrete. After the field rides outdoors, a clean, flat event floor is exposed with ample electrical outlets, fully ready to support non-cleat foot traffic to booths and other displays.

UofP’s $455 Million Stadium
Shimmers in the Arizona Sun
Photo: ESPN

Best known as the home of the NFL’s Arizona Cardinals and as the site of the NCAA’s Tostitos Fiesta Bowl, the building is not actually university property but a municipal sports arena whose naming rights were purchased by the for-profit University of Phoenix for marketing purposes.  Unlike most universities, University of Phoenix does not have an extracurricular sports program—yet sports are commonly a source of pride for university alumni. The school agreed to pay about $150 million for the 20-year naming arrangement, shortly after the Stadium was built in 2006.

When the grass field sits outdoors, the indoor stadium can be configured for a multitude of events: conventions, rock concerts, rodeos, and monster truck contests.  The University of Phoenix Stadium’s architects intentionally designed a multi-purpose dome, available for hosting various events 365 days a year, not exclusively a football stadium.

Golden Barrel cactus, Echinocactus grusonii
Photo: Priit Pensa

Its shape was inspired by the barrel cactus to announce its location in this Southwestern US desert city. Glendale receives an average of 306 days of sunshine per year.

The roof has two large retractable panels that can uncover the entire playing field or provide maximum shading for fans. In the hot months, the roof can be closed and the dome air-conditioned; in cooler months, the roof can be opened to take advantage of the Valley’s world-famous comfortable climate. 

It should be noted that the first domed sports stadium was the Houston Astrodome. Judge Roy Hofheinz conceived of such a structure in 1952 when he and his daughter were rained out of a minor league baseball game; the little girl asked her Dad: “Why can’t they play baseball inside?”

Hofheinz succeeded in building such a place in 1964--an 18-story-high, 710-ft diameter, air-conditioned dome! He also convinced Major League Baseball to send a franchise to Houston where, in this building, the weather would always be perfect. The dome even changed the initial name of the team. On April 9th, 1965, the Houston Colt .45s became the Houston Astros, introducing indoor baseball to the Astrodome fans and the nation.

The Astrodome opened with a natural Bermuda grass playing surface. Could natural grass grow in a stadium with little natural light? Since no good data were available at the time, a special greenhouse was constructed at Texas A&M University to test five different types of grass grown under low light conditions. A variety called Tiffway Bermuda grew the best and was subsequently planted in the Astrodome.

Houston Astrodome Configured for Football, 1965
Photo: EB

The dome’s ceiling contained 4,596 semitransparent plastic panes made of Lucite ®. Players quickly complained that glare coming off of the plastic panes made it impossible for them, even with sunglasses, to track high fly balls on sunny days.  The Astros surely didn’t want to play night games only. So all of the roof panes were painted over. This solved the glare problem, but, for lack of sunlight, it also killed the grass. For most of the 1965 season, the Astros played on green-painted dirt and dead grass! Baseballs hit into the outfield turned green. The Astrodome was about to become a sports fans’ joke—and then Astroturf was invented.

Artificial turf first came to major sports in 1965, when AstroTurf® was installed in that newly-built “wonder of the sports world”--the Astrodome in Houston, Texas. The use of AstroTurf® and similar surfaces became widespread in the 1970s, installed in both indoor and outdoor stadia for use by baseball and gridiron football teams in the United States and Canada. Maintaining a grass playing surface indoors, while technically possible, was often prohibitively expensive; teams that chose to play on artificial surfaces outdoors did so because of reduced maintenance costs and uniform surface coverage, especially in colder climates.

When turf toe became a sports injury commonly associated with playing on artificial turf, both the base and the fibers of artificial grass had to be improved. In addition, friction between skin and some types of artificial turf caused abrasions and/or burns to a much greater extent than natural grass did. This was an issue for some sports like football, where sliding is common and uniforms don’t fully cover the players’ limbs. More improvements were needed. Also, artificial turf tended to be much hotter than natural grass when exposed to the sun. Plants self-regulate their temperature, artificial turf does not. Again, engineering innovations were required.

The Anatomy of Astroturf XL
Image: Muhlenberg

Astroturf® is now in its 12th generation--from its original instantiation as ChemGrass by Monsanto, The short, scratchy, stiff, brush-type turf of past decades has been vastly improved. After many scientific studies of how players and balls move on real grass, it took lots of specialized machinery to manufacture and texturize an artificial grass that mimics the behavior of the real thing. Special sports footwear has also been designed for playing on it. Today’s Astroturf® is much longer and more lush, its fiber materials have been improved and its multi-layered base is now gently padded with rubber pellets. Today, a sister product, AstroLawn® is even used for architectural landscaping where natural grass is hard to grow.

Bottom line: It has taken over 40 years of research and development and countless patents to imitate natural grass satisfactorily, to make an artificial turf suitable for use on playing fields, without altering the nature of the game. Although these nylon and/or polypropylene fiber-based surfaces are quite expensive, they solve the “grass won’t grow well here” problem.  For example, with more than 3,000 installations and more than 225 million square feet of Astroturf® produced worldwide, on every continent and in more that 50 countries, it’s hard to deny its impact on sports—and that’s just one brand of synthetic turf.

However, indoors or out, many players still prefer to play on natural grass wherever it’s well-tended. Artificial turf injuries have ended playing careers. “It [artificial turf] should be banned,” Eagles defensive end Clyde Simmons said. “If they want to do something good, they’d get grass in here.” In contrast, some players actually like artificial turf because it allows them to run faster.

Concerns about the environmental impact of artificial versus natural grass playing surfaces continue. Both create a large amount of water run-off, adding to drainage loads. Chemical processes are used in the manufacture of raw materials for artificial turf, and harmful chemicals may leach-out over time. Conversely, biological grass in stadium applications requires potentially harmful chemicals, too, in the form of fertilizers and pesticides for maintenance.

Beginning in the 1990s, natural grass playing surfaces began to make a comeback when the marketing of nostalgia in professional sports resulted in the return of outdoor stadiums. Universities subsequently found that they were able to recruit better athletes if they could offer them a natural grass playing surface.

This series of photographs from Auburn University demonstrates the complexity of restoring a natural grass playing surface in a major football stadium. 

There are thousands of varieties of lawn grass, each adapted to specific conditions of watering, temperature, and sun/shade tolerance. Just as chemists and physicists continue to improve artificial turf, grass breeders continue to develop new and improved varieties of turf grass species.

An interesting recent development has been the hybrid playing surface of synthetic and natural grass. Once artificial turf is installed, it is top-filled with soil. Grass seed is planted in that soil, then grown to a height above that of the artificial turf. The resultant playing surface combines the look and comfort of natural grass with artificial turf’s resilience and resistance divots and gouges. Unfortunately, the hybrid also requires all the maintenance of both turf systems and it’s unsuitable for most indoor applications. Advances continue.

Inside the University of Phoenix Stadium, Site of Super Bowl XLII--2008
Photo: Lectrosonics

Turf management isn’t typically a career that high school students consider, but it is a growing and rewarding field— one that includes the benefits of working outdoors. One can actually pursue a major in Turf Management at several US universities. Turf Management students learn how to plant and care for lawns, parks, recreation areas, golf courses, and athletic fields. Classes address horticulture, botany, biochemistry, agronomy, planting, transplanting, and caring for grasses and related plants, irrigation, and landscape design.

Cristina Milesi, who has estimated that there are 40 million acres of lawn growing in the US, points out that turf is our nation’s largest irrigated crop. Americans do enjoy their lawns. Now about 2.1 acres of it can go indoors to play or move outdoors to maintain its vitality.  In addition to watching the New England Patriots and the New York Giants play in the 2008 Super Bowl, don’t forget to take a look at the ~106 million blades of natural grass making those great plays possible, and providing a backdrop for all the action!  Move the Earth, Archimedes? Indeed!

Friday, January 18, 2008

Diversity: Madagascar v. NYC

A “new” species of palm has been discovered on the island of Madagascar, thanks to its flowering finale.

Blossoming to the end
Tahina spectabilis
Photo: Xavier Metz

Botanists around the world are popping the corks over Tahina spectabilis, a gigantic palm tree just discovered in the northwest of Madagascar, even though the plant, blooming its head off, is about to die. ”Details of the flowers and branches suggested it was a species and genus of palm that had never been described before,” reports the Guardian. “Genetic tests on the plant confirmed that it comes from an evolutionary line that was not previously known to exist in Madagascar.”

Actually, plant discoveries have been coming pretty fast and furious on this big island off the east coast of Africa. “Out of the 10,000 plants native to Madagascar, 90% of them are found nowhere else in the world.” The huge palm gave itself away with a spectacular show of flowering.

Whereas most palm trees bloom periodically throughout their lives, this giant shoots the moon. “Once it is fully grown, the tip of the stem branches into hundreds of tiny flowers that sap nutrients from the plant so rapidly that it collapses.” On a stroll with his family, Xavier Metz, the manager of a nearby cashew plantation, spotted the huge flower stalk cascading in the sky. He took pictures and posted them on the web, attracting the attention of the plant experts at Kew Gardens and botanists around the world.

Tahina spectabilis
Photo: Xavier Metz

“Ever since we started work on the palms of Madagascar in the 1980s, we have made discovery after discovery,” said John Dransfield, an English scientist. “But to me this is probably the most exciting of them all.” Tahina spectabilis is a thrill for several reasons: its size (some say it grows ”six stories tall”), its novelty, and its dissimilarity from other palms thus far found on the island.

Press releases said that the tree was named for Metz’s daughter Tahina, and that “‘Spectabilis’ means ‘blessed’ or ‘to be protected.’” But we side with the Ethical Paleontologist, who believes that Tahina must mean “blessed” in Malagasy (whether it’s Metz’s daughter’s name or not); and “spectabilis” means, well, “Geez, lookadat!”

Bioclimates of Madagascar
Map: Missouri Botanical Garden

Madagascar owes its immense plant diversity primarily to two features: its range of climate zones and its isolation. There are tropical rainforests on the island’s eastern side, while the west and south, “in the rain shadow of the central highlands, are home to tropical dry forests, thorn forests, and deserts and xeric shrublands.” This shoot-the-moon palm tree was discovered in yet another bioregion, the northwest part of the island. Check out the map at right, via the Missouri Botanical Garden, which has a concerted plant research project of its own ongoing in Madagascar.

We find it curious that in the plant world, isolation is so conducive to diversity, whereas in the human social world, those environments that are least isolated tend to be the most diverse (New York City versus North Dakota). Cities seem to attract ethnic complexity, even as they destroy it—melting down distinctions in the longer run. There is a case to be made for geographic isolation in human culture, too. We think of Gee’s Bend, a particle of land cut off by a loop in the Alabama River. The society of Gee’s Bend is not in itself diverse, but its relative isolation fostered an original flowering of its own, rare and spectacular as a six-story palm. ”Gee’s, lookadeese!”

Sunday, January 13, 2008

Behold the Wollemi Pine!

With the discovery of “living fossils” in China and, now, Australia, the EarthScholars administer a gentle bump on the head. Wake up! You might have just missed a plant celebrity. Thank you, Jim and Renee.

Through One Eye
By Joan True (1940-2006)

By James H. Wandersee and Renee M. Clary
EarthScholars™ Research Group

It seems rather “common sensical” to us that when we look at something repeatedly, we observe whatever is present to be seen, and over time, it becomes increasingly familiar to us. But is that really a defensible assumption?

Shall we conduct a little test? Surely you have watched the fingers on your hands move countless times. If you are currently sitting at a table, position one of your hands forcefully flat on the table top in front of you.  Question: Which finger is the only one that cannot be easily lifted up by itself, separately, while the remaining four are kept flat?  Although most people have looked at and used their fingers every day of their lives, few people predict that it is their ring finger which has the least dexterity. Why don’t they know this? Visual cognition studies show that we often “look” without selectively paying attention to or concentrating on particular aspects of our visual field.

Thus, the verifiable but seldom chosen answer is the ring finger—for anatomical reasons that turn out be fairly complex. However, and this is important, if you were guided by a mentor to observe your fingers systematically for an extended period of time--such as in learning to type, to play a musical instrument, or to perform sleight-of-hand magic tricks--you are much more likely to answer that question quickly and correctly, based upon your visual memory of your own finger movement. Thus, observation is really “systematized looking” that we consciously wish to make available to us for future recall—this happens whenever we are looking with a vested interest or a purpose in mind, or whenever we are looking carefully in order to try to understand something.

Another example: How many times have you looked at a US penny? Thousands of times! You get pennies in change and you count them; you lay out your pennies to pay a restaurant bill exactly; you place your pennies in a coin dish for later use. You don’t do these things with your eyes closed, do you? Questions: Does the president’s head on a penny face right or left? Which US president is it? How many times and where does his image appear on a single penny? On which side and at which clock-hour position does the word liberty appear? Is it written as LIBERTY or Liberty? It’s not easy to recall these details, is it?—unless you are seasoned numismatist (coin collector). If so, you are used to observing these features and using them as indicators to establish the grade or condition of each penny in your collection. Similar limitations apply to the untrained eye’s observations of plants, but to an even greater degree—because most people look at individual plants quite infrequently.

In our January 10th, 2006 Human Flower Project article entitled “On Seeing Flowers: Are You Missing Anything?” we explained the basic principles of our plant blindness theory which asserts that, especially in urban settings within developed countries, people tend subconsciously to overlook, undervalue, and fail to differentiate the plants in their environment—consciously sensing only a “green blur” or a verdant backdrop of vegetation against which human and animal activities of interest to them take place.

It should be noted that the United States is an urbanized nation, with 80% of its population residing in cities and suburbs. Thus, it seems likely that, unless they have been influenced by a plant mentor or are self-taught plant aficionados, plant blindness is the default botanical- attention state for most US citizens today.

People pay more attention to large plants than small plants. The largest plants in the Plant Kingdom are trees (which, studies have shown, young children don’t even consider to be plants). Trees comprise about 25% of all plant species and are the defining life forms of many large terrestrial biomes--including the temperate coniferous forest biome, deciduous forest biome, and tropical rainforest biome. You would think that by the present day, humankind would have discovered all the large species of trees on Earth—and you would be wrong. How could even experienced plant explorers overlook some strange-looking, tall trees, you may ask?

The discovery site of the Wollemi Pine
Image: Bradshaw Foundation

Consider this. In 1994, approximately two dozen 100-foot-tall trees from the age of dinosaurs (90 million years old) were discovered growing in the sandstone gorges of a wilderness area only 125 miles northwest of the most populous city in all of Australia—Sydney, the home of over 4 million people.

These trees were discovered in Wollemi (WALL-um-eye) National Park of New South Wales by David Noble, a bushwalker/rock climber/park and wildlife officer. Having previously made hundreds of expeditions exploring the park, Noble was an experienced plant observer who suddenly realized he had never seen such trees before. He stashed several twig specimens in his backpack to show to expert dendrologists (tree biologists) and plant taxonomists.  The trees that caught Noble’s attention turned out to be an entirely new tree species, and even a new genus of tree, apparently related to the ancient Araucariaceae (ah-rou-carry-ACE-eh-ee) family of evergreen coniferous trees, a family dating back 200 million years. Other members of this family include the Norfolk Island Pine (Araucaria heterophylla) and the Monkey-Puzzle tree (Araucaria araucana).

In 1998, these newly discovered living trees were officially named the Wollemi Pine (Wollemia nobilis), with the species epithet nobilis honoring its discoverer, David Noble. Part of its common name, Pine, is (as with the Norfolk Island Pine) a misnomer, because this tree merely resembles a pine (true pines are members of the genus Pinus and are typically found only in the Northern Hemisphere).

Wollemi Pine: Fossilized leaves and living leaves, in two or four flattened ranks
Photos: Paula Offutt

Later, paleobotanists discovered that existing specimens of fossil pollen and fossil seed cones (including some recovered during Australian dinosaur excavations) matched those of the living Wollemi Pines. There is now quite a well-established fossil record of this species. Journalists often call such a plant species a living fossil: an informal term for any living species (or clade) of organism that appears to be the same as a species otherwise only known from the Earth’s fossil record and that has no close living relatives.

In paleobotany, a Lazarus taxon (plural, taxa) is a classification category that disappears from one or more periods of the fossil record, only to appear again later. (The term refers to the biblical story of Lazarus, whom Jesus miraculously raises from the dead.) Lazarus taxa are observational artifacts that can occur due to incomplete sampling or local extinction in areas later resupplied. In the case of Wollemia nobilis, some existing fossil pollen and seed cones were shown to have been previously misidentified, and thus some gaps in its fossil record have now been eliminated.

Artist’s rendering of a Wollemi Pine
Image: Edge Cinema

Later scientific studies have shown that Wollemi Pines
(a) total about 100 mature naturally-occurring, living specimens, divided into three small populations within the park;
(b) populations reproduce sexually but show virtually no genetic variation—these trees are all clones;
(c) are susceptible to attack by foreign pathogens carried by visitors (hence researcher access has been carefully controlled via quarantine at the three secret natural sites within the park and $133,000 fines are posted for disturbing these trees);
(d) are strangely capable of shedding entire branches rather than just individual leaves;
(e) are host to a fungus which produces taxol, an important anticancer drug;
(f) can be raised from seed, plus be successfully propagated quite rapidly using modern tissue culture techniques;
(g) are found in three similar ecological niches featuring permanently moist, active-stream gorges, with similar soils and light regimes; and
(h) often have multiple stems originating at the base of their trunk--as many as 160.

The Australian government has helped the Wollemi Pine become a plant celebrity. Potted specimens were sent on tour to the nation’s botanic gardens. Sydney’s botanic garden organized a cooperative venture between the government and the private business sector to use tissue culture techniques to propagate and sell the tree on a commercial scale, with an international marketing plan.  Royalties from its plant sales will support conservation of the Wollemi Pine. Thus, North Americans can now order their own “living fossil” Wollemi Pine tree (check here) for a cost of less than $150. It can be cultivated as a tall tree, patio plant, or potted plant. Because this ancient and initially rare tree has attractive, unusually dark green foliage and bubbly (coco-puff-like) bark, sprouts multiple trunks, and is shade-tolerant, it is quite likely to become popular worldwide, both as a plant celebrity and geobiological teaching tool to heighten public understanding of plant evolution, biodiversity, extinction, refugia, and geologic time.

Plant zoo? Rare Wollemi Pine exhibited inside a cage for its own protection
Photo: Biotechnology Online

In 1948, the announced rediscovery of the Dawn Redwood tree (Metasequoia glyptostroboides) in China near Modaoxi by Zhan Wang (1943)—a tree previously known only by its fossils—rocked the botanical world. It is the only living species in the ancient redwood genus named Metasequoia. An easy tree to grow from seed in temperate climates, it can reach a height of 135 feet or more within a century after planting. Or, if you have no room in your yard for such a tall tree, you can grow one as a miniature bonsai tree.

As if to anticipate the focus of this article, it should be noted that Wollemi is an aboriginal word meaning “Watch out!” or, “Look around you!”

Our message is that paying attention to plants necessarily involves comparison and attending to details. We often look without seeing, without knowing what to look for, and thus we miss much more visual information than we should. Two other hikers accompanied David Noble on the day of his great discovery, but only David noticed the huge Wollemi Pines. The emotional, intellectual, and participatory rewards of careful plant observation can help give our lives and the lives of others meaning and purpose. That’s what David Noble’s and Zhan Wang’s discoveries teach us. As for the Wollemi Pine, Sir David Attenborough spoke for the embedded biological explorer that resides within each of us when he exclaimed: “How marvelous and exciting that we should have discovered this rare survivor from such an ancient past.” A plant celebrity? Indeed!

Tuesday, January 08, 2008

Swedes Do It Differently

An exhibit of floral photographs shows the ranging sexuality Linnaeus saw, recorded, loved.

Tragopogon pratensis
from Herbarium Amoris
by Edvard Koinberg

Could it be that a culture’s sex life is revealed in its floral art?

An exhibit of photographs by Edvard Koinberg called Herbarium Amoris suggests that may be.  Koinberg shots and assembled 38 flower images to celebrate botany’s first librarian, Carl Linnaeus of Sweden (his 300th birthday was last May). Koinberg points to Linnaeus’s candid and loving study of plant sexuality as the inspiration for his own art.

“Flowers are nothing other than the breeding organs of plants,” Linnaeus wrote, “yet with that difference from those of animals, which we regard as so foul that witnessing them awakens shame, so that, in animals, nature has in most cases found a way to cover them up. On the other hand, in the plant kingdom these parts are not hidden but instead firmly exhibited for all to see, Oh, yes!”

Koinberg writes that with Systema Naturae‘s publication in 1735, it took only two months for Linnaeus to become famous. “His ideas concerning the sexuality of plants caused some alarm, but people were also titillated by them. He was accused of leading young people astray with his accounts of the plants ‘love life.’ This, however, simply added to his reputation.”

There’s nothing new about titillation leading to celebrity. But a couple of things make this exhibit enormously interesting. First, the Swedish Institute, a state agency “established to disseminate knowledge abroad about Sweden´s social and cultural life” has sponsored Koinberg’s show and made possible a three-year global tour. Now, certainly MGM and Warner Brothers are only too glad to disseminate (sorry) U.S.A.-style sexuality abroad, but the U.S. government?? Not in 300 or even a million years.

Secondly, Koinberg’s interpretation—the depiction of sexuality in his flower photographs—is quite astonishing, especially for those of us accustomed to the sleek, quasi-pornographic breast and phallus imagery of Americans like Robert Mapplethorpe. What a shudder, that we’re invited to see the amorousness in an image like this:

Paeonia lactiflora

Or how about this?

Dryopteris flix-mas

It’s not too late for New Year’s resolutions!!

Readers who investigate the Swedish Institute’s site can explore Koinberg’s work in the same spirit as Garbo-watching: without one bit of “shame.” Another delight is to see the variety of ways that Herbarium Amoris has been installed across the world. Perhaps there are clues to sexual behaviors here as well; keep it elevated, oh yes, and tell us what you find.

The Orangery Garden in Österbybruk, Uppland, Sweden (2005)
Photo: Herbarium Amoris

The exhibit continues its tour this year; here’s a rough schedule:

8 Jan. - 16 Mar. 2008: House of Sweden, Washington D.C. USA
15 - 27 January, 2008: Angebo Folkets Hus, Sweden
13 Mar - May, 2008: National Museum of History, Minsk, Belorussia
Sept - Oct. 2008: Museum of Nature History, Belgrade, Serbia