GardenDesignOnline

DNA Tests to Combat Florida's Invasive Pines

Australian pines were first brought to the United States in the early 1900's as lovely ornamental shade trees, thought to be a perfect solution for many yards in hot, sunny sites.  The "pine" is now a troublesome invasive plant that has escaped into the wild in south Florida, the Virgin Islands, Puerto Rico and Hawaii.  The plant, which is not related to our north American pines, has become a highly invasive problem weed that is choking out native species in southern US coastal areas, and it is a particular problem in Florida's Everglades National Park.  It is commonly referred to as ironwood, horsetail tree, or Australian pine.

There are actually three different species of Casuarina -- C. equisetifolia, C. glauca, and C. cunninghamiana,  but the three look so much alike that it is very difficult to tell them apart.  Scientists at USDA's Agricultural Research Service are now conducting research to positively identify each species by its specific DNA and then finding insects for each one that might be used as biological control agents.

ARS scientists have traveled in recent years to Australia, where they collaborated with Australian colleagues to collect DNA samples from native Australian trees and to identify insects that might be used to stop the spread of the plant in the United States and its territories. ARS entomologist Greg Wheeler says that although Casuarina has some "fine qualities ... its negatives far outweigh its positives."  Wheeler and Australian scientists collected over 300 insects that might be used to control the weed, and narrowed the field of potential control agents to just 12, including a wasp that eats the plant's seeds and a moth that attacks the foliage.

By the end of this year, the researchers expect to complete their DNA studies, which will allow them to positively identify which species is which -- and then match them with an insect that will help stop the spread of a now-deadly plant that inhibits the growth of native American species.

(image: ARS, courtesy Amy Ferriter, S. Florida Water Management District, Bugwood.org)

Skyscraper Gardening

More and more people around the world are moving off the farm and into cities ... and if the world's population keeps growing, will there be enough land to grow the crops needed to sustain all the people?

Columbia University Public Health Professor Dickson Despommier, a microbiologist and ecologist, has been asking those questions and coming up with some interesting answers.  For the past several years, Dr. Despommier has been advocating vertical farming -- on skyscrapers -- and has lined up some architects to design "living towers" where urban residents could raise food crops.

An article in today's New York Times, which you can read here, says the idea has caught on with Manhattan borough president Scott Stringer, and his office plans to urge the mayor's office to think about a vertical farming pilot project.

According to Dr. Despommier's website, The Vertical Farm Project, 80 percent of the world's cropland is now in use, and by 2050, there will be an additional three billion people on earth.  One solution for farming could well be vertical farming, with new cutting-edge technologies to make the "farms" economical and sustainable. "The time is at hand," he says, "for us to learn how to safely grow our food inside in environmentally controlled multistory buildings within urban centers.  If we do not, then in just another 50 years, the next 3 billion people will surely go hungry."

Food for thought.  And check out some of the stunning architectural designs on the Vertical Farm Project website.

(images: Vertical Farm Project)

The White House Grows

Roosevelt Redux?

Presidents like to rip up the records of their predecessors, and that includes changes on the grounds of the White House.  Reagan ripped off the solar panels that Jimmy Carter installed on the mansion, and there's no trace today of the Victory Garden planted by the Roosevelts. 

So in this time of climate change and high fuel prices, Roger Doiron thinks it's time to "Eat the View" at the White House.  In an interview with Garden Design Online, Doiron, founder of Kitchen Gardeners International, said he's urging the next president to re-plant "an edible landscape" at the White House as an example to all Americans to conserve energy.

Doiron points out that it takes 10 calories of fossil fuel to produce every one calorie of food consumed.  Put another way, the average food item in the United States travels 1500 miles to get to your plate -- and costs 400 gallons of fuel.

Greening the Dog

For all green roof fans afraid to try one on your own home:  experiment with your dog.

The June 3rd Home & Garden section of the Los Angles Times has an article about dog houses with green roofs designed by landscape designer Stephanie Rubin and her partner, sculptor Chris Isner. They go for around one to four thousand dollars, but the article says you can make one yourself for much less.  They keep the dog cool, and the roofs are planted with natives that are animal-friendly.  Read more about it here.  Or try the company's web site, www.sustainablepet.com.

Edible Front Yards at Descanco

Architect Fritz Haeg has recently installed one of his edible front yards at Descanso Gardens in La Cañada Flintridge, CA. You can read an article about it in the Pasadena Star News (scroll down for article), or see pictures of the installation here from Descanso itself,  and decide for yourself whether you should try it out on your own landscape.

FYI, I reviewed Haeg's book in a post earlier this year.

Energy-saving Greenhouse

The Cleveland Botanical Garden and Kent State University's Liquid Crystal Institute (LCI) have unveiled a new research project to explore the use of liquid crystal panels to create energy-efficient greenhouses.  Two 8x10' greenhouses have been constructed at the botanical garden -- one with plain glass panels and the other with liquid crystal panels. Over the next several years, researchers will compare plant growth, temperature, light levels, and energy used in each greenhouse.

The Cleveland Botanical Garden's executive director, Natalie Ronayne, says the basic goal is "to design a smart greenhouse."  She explained that the liquid crystal panels can regulate the amount of sunlight reaching plants inside.  The LCD greenhouse has a photo receptor inside that can be programmed for specific plants, according to the amount of light they need. "If you program it to have a certain amount of light and it's a cloudy day, the windows will never become foggy -- they will stay fully on to attract and absorb as much light as possible from the spectrum," said Ronayne. "If it's really sunny and it's a hot day ... the windows will automatically dim to control the shading."

The experimental greenhouses house a variety of plants -- tomatoes, peppers, petunias, lilies, orchids, and more. Ronayne said the experiment will last for at least two years -- to measure plant growth, monitor energy bills, and test the durability of the LCD windows.

The hope is that by controlling the amount of light coming into the greenhouse, costs for heating and cooling major greenhouses will be reduced. 

Air Pollution Impedes Pollination

Researchers at the University of Virginia have found that air pollution from power plants and vehicles destroys the scent of flowers, making it difficult for pollinating insects to follow fragrant aromas to their source.

The study indicates that diminishing scent trails could be a reason for declining populations of pollinators, particularly bees.   Jose Fuentes  (center in photo) professor of environmental sciences at the University of VA and co-author of the study, said that "scent molecules produced by flowers in a less polluted environment, such as in the 1800's, could travel for roughly 1000 to 1200 meters; but in today's polluted environment, downwind of major cities, they may travel only 200 to 300 meters."  Fuentes noted that this makes it very difficult for pollinators to locate flowers and the nectar they need for food.

Fuentes and his research team found that scent molecules produced by flowers are very volatile and bond with pollutants such as ozone that destroy their odors.  Therefore, the scents are chemically altered and destroyed, and when they travel on the wind, they no longer have the aroma of flowers.  The scientists believe that the pollinators are having to search longer distances to find sources of food, and perhaps are relying on sight instead of smell.

"It quickly became apparent that air pollution destroys the aroma of flowers by as much as 90 percent from periods before automobiles and heavy industry," said Fuentes.  "And the more air pollution there is in a region, the greater the destruction of flower scents."

The entire study appears online in the journal  Atmospheric Environment.

All the more reason, readers, to get on the "green" bandwagon.

Redwoods vs. Sunpower

I first heard about the redwood controversy at a lecture earlier this year by Conard Pyle president Steve Hutton.  It's hard to believe that neighbors in California are fighting over solar panels and large trees that block the sunlight, but a state law has actually been enacted to protect environmentally minded homeowners who don't want their neighbors to plant tall trees that block their sunlight.  Read all about it in this article from the New York Times.

A Big Hitch in Outdoor Living

If you talk to any high-end landscape designer, they'll tell you that one essential in any garden these days is fire outdoors:  a firepit, a fireplace, a chimenea, almost anything that glows in the dark and heats the place up a bit on chilly nights.

BUT -- from Connecticut to the Chicago suburbs, to California and Canada, municipalities are either considering or imposing bans on wood burning outdoors.  And that includes a lot of fancy and expensive new garden amenities.

You may be able to get away with gas-fired modules like those shown here (by FireByDesign), but anything that burns wood is now taboo in large swathes of California and in many other municipalities across the country.

Earlier this month, California's South Coast Air Quality Management District approved strict new regulations on wood burning fireplaces that affect homeowners in Orange County, parts of Los Angeles, Riverside and San Bernadino counties.  The new rules are in line with others already in existence elsewhere in the state. The wood-burning ban is aimed at reducing fine particle pollution, including bits of soot, which can work their way into lungs and cause a variety of health problems, including asthma, heart attacks and lung diseases.  The regulations cover indoor and outdoor wood-burning fireplaces, as well as chimeneas, back yard firepits, and other devices that burn wood.  Beach bonfires are not included in the ban, nor are wood-burning cook stoves, such as pizza ovens.  Within a year, wood-burning fireplaces in all newly-constructed homes will be banned completely.

In the Chicago suburbs, a group called Breathe Healthy Air is pushing for a ban on second-hand smoke that comes from wood-burning stoves and fireplaces, and similar campaigns are taking place in communities across the country.

While an outdoor firepit or chimenea can be relatively inexpensive, a real outdoor fireplace could cost tens of thousands of dollars.  Designers and homeowners should be aware of the trend taking hold in many states before they shell out thousands of dollars on something they might never be able to use.

(image: FireByDesign)

A "Green" Grower

Steve Hutton, President of Conard-Pyle, Inc., is a grower with a vision. He spoke recently at a regional meeting of the Garden Writers Association and gave an astonishing presentation about his company's efforts to promote sustainability and protect the environment.  You've all heard the bad raps about growers -- that they're not concerned about invasives or pesticides or trucking plants for thousands of miles -- they're just in it for the money. 

Hutton has thought hard about of lot of these issues, and Conard Pyle is making every effort to be eco-friendly.  Consumers are one of the company's biggest problems.

Here's a photo of a pink "Knockout' shrub rose growing next to a 'Mr Lincoln' hybrid tea. No pesticides or fungal sprays were used on these plants, and while 'Knockout' is doing fine, 'Mr. Lincoln' is definitely struggling. Despite the plant's problems, Conard sells thousands of Mr. Lincolns every year. Hutton told us if he were in the toy business, the government would probably shut him down.

Hutton advises planting more natives, but he says they are usually the last thing consumers want.  When they show up in the nursery, he says, they look at a plant and ask "Does it do anything?"  Hutton is high on the native Viburnum nudum 'Winterthur,' but in the plant's home neighborhood of the Delaware Valley (PA), Conard Pyle sells 10 Mr. Lincoln roses for every V. 'Winterthur.'

(click on image to enlarge - image: Conard Pyle Inc.)