Native plants are emerging as the new heroes in a growing struggle to deal with climate change. In communities that consistently have too little water, drought-tolerant mesquite trees, buffalo grass, and colorful Texas red sage provide attractive landscaping that doesn't require watering. Native plants also come to the rescue in areas with the opposite problem – storms that dump heavy rainfall and overwhelm the infrastructure for dealing with storm water. There, plants such as marsh milkweed, cardinal flower, bloodroot, and great blue lobelia can soak up the excess before it can run off.
Native plants are trees, shrubs, and wildflowers that grow in a specific region where they have evolved over time, adapting to the prevalent environmental conditions. Because of this, they can conserve water resources more efficiently than nonnative plants, which are naturally adapted to other climates.
In Denver, where the water-conserving landscape movement known as xeriscaping was launched in 1981, one of the first efforts in the city's sustainability program saw the Mile High Youth Corps replanting large areas of lawn with flower beds of drought-tolerant native plants at Denver's City and County Building and in front of three area recreation centers.
These conservation gardens – and the many others that followed – are one part of Denver's sweeping environmental initiative called Greenprint Denver (www.greenprintdenver.org).
Before Greenprint, the city made decisions about infrastructure, purchasing, land use, transportation, and waste management based on their social and economic impacts. Now, says Beth Conover, director of Greenprint Denver, environmental effects are being considered as well. "Greenprint is an effort to make sustainability a core value and operating principle of everything we do."
The program's goals include conserving water, reducing greenhouse emissions, using renewable energy, reducing waste, promoting mass transit, and increasing the amount of "green" housing that's affordable.
"Greenprint Denver sets an action agenda for sustainable development," Mayor John Hickenlooper says. "Every agency of the city government has to pass through the filter of Greenprint." All agencies – from parks and recreation to waste management – must consider and follow policies and practices that encourage environmental health, economic opportunity, and smart growth strategies.
One of Mr. Hickenlooper's goals for Greenprint is to get more people and organizations involved. "If everyone plays a part, it's not as daunting a task," he notes.
One example of a growing collaboration will occur later this month. As a kickoff to the mayor's plan to plant 1 million trees over the next 20 years, at least 7,000 new trees will be planted between Earth Day (April 22) and Arbor Day (April 27). "More than 42 different municipalities and organizations are participating," Hickenlooper says. "Now it looks like we might plant 9,000 or 10,000 trees."
Denver's mayor is committed to conservation on the personal front, too. In addition to turning down the thermostat at home and driving an energy-efficient vehicle, he washes and reuses his plastic sandwich bags. "We also xeriscaped as much as possible," he adds.
Native plants ease storm-water runoff
In Kansas City, Mo., where rain often causes flooding, native plants are providing a creative solution to managing storm water. The 10,000 Rain Gardens project is a communitywide environmental initiative designed to improve the quality of water flowing into streams, rivers, and lakes. (See www.rainkc.com and www.kcmo.org/mayor.nsf/web/raingarden?opendocument.)
Rain gardens are strategically placed in low spots in the landscape and designed to catch and hold rainwater, preventing it from running off the site. (Runoff causes flooding and is also responsible for polluting waterways with fertilizers and pesticides.) When planted with water-loving native plants, a rain garden becomes a beautiful and functional landscape addition that captures water before it can cause problems.
Lynn Hinkle, the project manager, is working to rally the community to build 10,000 individual rain gardens over the next five years.
"This is a 21st-century version of the Victory Gardens promoted during the Second World War," Ms. Hinkle says. "Water is the 21st-century commodity that will most impact hunger, health, and human life on the planet, and this is part of the solution."
Rain gardens are becoming a popular method for controlling storm water in the states of Oregon, Michigan, and Minnesota. But no other city has embraced the idea of getting its citizens involved in building 10,000 rain gardens, Hinkle says.
The campaign was embraced by residents in early 2006. "Mayor Kay Barnes really understood the issue and engaged the public to help relieve pressure on aging storm-water systems by capturing raindrops where they fall naturally," Hinkle adds.
Corporations, as well as individuals, are participating in the project. The Kansas City Art Institute, in partnership with the Brush Creek Community, is building a rain garden designed by its students. And Hallmark Cards is also planning a large rain garden at its headquarters in the city.
Nearly 200 individual rain gardens have been registered on the project's website, and one of those is in Hinkle's yard. She says that her basement flooded during heavy rains before she installed her rain garden. During a recent storm, she was pleased to see that the basement remained dry. "I'm pretty excited about what I've done in my own backyard," she says.
Landscaping that needs little water
While native plants help Kansas City residents deal with too much water, native species in New Mexico help conserve it. Intel, one of the world's largest makers of semiconductor chips, invested $1 million to add drought-tolerant plants to 50 acres at its Rio Rancho facility.
By xeriscaping the entire east slope of the factory grounds with more than 2,000 native trees and shrubs, Intel significantly reduced its need for irrigation water. Because the landscaping project includes a path almost a mile long that connects the Rio Rancho, Corrales, and Skyview communities, the residents of those neighborhoods provided input into the design.
"Part of being a good corporate citizen is looking for opportunities to improve water efficiency in every aspect of our operations, from making the ultrapure water for the manufacturing process to using water in the landscape," says Dave Stangis, director of corporate relations.
In addition to the xeriscape project, Intel is improving its water efficiency by reducing the amount of water used during production and by reusing and recycling that water.
"Intel invested $20 million to make the process of turning tap water into ultrapure water more efficient," says Mr. Stangis. He adds that the company has saved 3 billion gallons of water over the past eight years by reusing and recycling the ultrapure water instead of using fresh water for its operations.
Meanwhile, at the Highlands Center for Natural History in Prescott, Ariz., native plants are helping to educate the next generation of scientists, conservationists, and architects. The center (www.highlandscenter.org) is committed to helping children and adults become wise caretakers of the land.
Conservation concepts are woven into every program at the Lynx Creek Site, an 80-acre classroom without walls that it operates in the Prescott National Forest. Executive director Nichole Trushell has modeled the center's learning philosophy on her own experience. She says roaming in the woods inspired her to become a botanist.
In addition to the outdoor experiential learning, the campus itself is a model for ecofriendly green building concepts and conservation. A new learning center generates the electricity it needs by using solar panels and a battery backup system. The center's butterfly roof has its low point in the center to direct rainwater at two points toward native plantings.
A maintenance building sheds rainwater into collection tanks, which is then used to enhance constructed wetlands that treat the center's waste water.
In the future, the center will plant an arboretum to showcase the native plants it offers during its biannual public plant sales. The arboretum will also serve as a living demonstration of how native plants help conserve water in the landscape.
Whether saving irrigation water, improving water quality, or teaching lessons in conservation, native plants are doing their part to help the environment, just as nature originally intended.