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PNW Native Plants for the Landscape:
Groundcovers:
Kinnickinnick (Arctostaphylos uva-ursi)
Squaw carpet (Ceanothus prostrates)
Salal (Gaultheria shallon)
Creeping Oregon-grape (Mahonia repens)
Shrubs:
Vine maple (Acer circinatum)
Saskatoon serviceberry (Amelanchier alnifolia)
Snowbrush ceanothus (Ceanothus velutinus)
Red-osier dogwood (Cornus sericea)
Twinberry (Lonicera involucrate)
Oregon Grape (Mahonia aquifolium)
Mockorange (Philadelphus lewisii)
Pacific Ninebark (Physocarpus capitatus)
Red-flowering currant (Ribes sanguineum)
Salmonberry (Rubus spectabilis)
Snowberry (Symphoricarpos alba)
Evergreen huckleberry (Vaccinium ovatum)
Trees:
Red alder (Alnus rubra)
Pacific madrone (Arbutus menziesii)
Paper birch (Betula papyrifera)
Pacific dogwood (Cornus nutallii)
Quaking aspen (Populus tremuloides)
Bitter cherry (Prunus emarginata) |
Eco (–logically and -nomically) friendly landscaping with PNW Natives
By Seth Swanson, CPH
Lawyer Nursery
Recently there seems to be a shift in the overall ideals of the consumer, as people are becoming more and more environmentally conscious. This may be attributed to reports of global warming or to the ubiquitous rising costs of fuel. Regardless, identifying the damages that have been done and are being done to the environment is an important start. But, making lifestyle changes, no matter how modest they may be, to alleviate these global stresses is an important step to preserving the environment and enriching our lives and of those to come. Many consumers are trading in their gas-guzzlers for hybrid or more fuel-efficient vehicles that consume less fuel and contribute less to the build up of atmospheric carbon dioxide (a main constituent in the global warming process). Another increasing consumer trend in the current environmental mindset is the consumption of organic commodities. Organic products are not necessarily safer to consume than conventional products, but are generally more environmentally safe to produce. Organic foods do not incorporate the use of any conventional pesticides, fertilizers, animal growth hormones or antibiotics. Therefore, there is generally less of an environmental impact during the production of these products. Another way which consumers are becoming proactive in moderating environmental strains is by planting native vegetation. Some are converting residential turf and introduced landscapes into native plantings while others are planting native species for restoration or remediation projects. Planting native species will have many benefits to both the environment and your pocket book, which is an ideal solution during a time when both may be under significant stress.
Once established, native plants require little to no supplementary applications of pesticides, fertilizers, and water. Native plants are able to survive without these staples needed by introduced species because they have adapted to grow in the regional conditions. Native plants may have modified organs that aid in nutrient and water uptake as well as storage as adaptations to local environmental conditions. Some well-known examples of these adaptations are; cacti, which are equipped with a modified stem to store water to accommodate survival in arid climates, and many legumes, which can form symbiotic relationships with soil bacteria to fix atmospheric nitrogen and flourish in otherwise nitrogen limited soils.
A major source of pollution and ground water contamination comes from the urban landscape in the form of fertilizer and pesticide runoff. In a publication produced by the U.S. Environmental Protection Agency, researchers at Cornell University found that 60% of nitrogen applied to turf was leached into the groundwater of a New York community, and this may be greater in coastal areas that have more porous soils. High levels of fertilizers leached into waterways and the groundwater can cause significant problems. High levels of nitrates in drinking water can be detrimental to infants, and elevated levels of nitrogen and phosphorous, which are primary components of fertilizers, can be harmful to natural ecosystems, and can stimulate algae blooms in open waterways. These algae blooms can cause a significant drop in dissolved oxygen levels of the water system and thus killing fish, amphibians, and aquatic plants. The production of synthetic fertilizers require a considerable amount of fossil fuels, something that has become somewhat limited and definitely more valuable in today’s society. The EPA states that over $5 billion is spent on fossil fuel derived fertilizers for U.S. lawns every year.
In addition to the reduction of fertilizer use, native plants generally have a reduced demand for water compared to introduced species. Water conservation should be of concern to everyone in the Northwest as we may be facing eminent drought this summer as a result of low winter snowpack. Even during periods of significant water shortage, lawns, golf courses, and landscapes are still being irrigated. The U.S. EPA states that 30 to 60 percent of urban water is used for watering lawns, the larger values generally occurring in the west. Planting native plant species, which are already adapted to local climate and annual moisture levels, can eliminate this luxuriant use of water.
Pesticides are another major source of groundwater pollution originating from urban landscapes. According the U.S. EPA, an estimated 67 million pounds of synthetic pesticides are used on U.S. lawns every year at an estimated cost of $700 million. Like fertilizers, pesticides too can leach into the groundwater and waterways potentially contaminating both drinking water and natural ecosystems. Not only are many synthetic pesticides potentially hazardous to human and animal consumption, they also are generally not specific in the genera of insects being killed. There are many beneficial insects living in the landscape, which can naturally reduce insect pests also inhabiting the surrounding area. Native plant species are adapted to the local conditions and are therefore resistant to most of the local pests, thus reducing the need for pesticide use. Planting native species will reduce the need for pesticide and fertilizer applications. This will both alleviate additional environmental contaminations from landscape runoff and reduce annual costs of the landscape.
In addition to reducing synthetic contaminants into the environment, greenhouse gasses may also be reduced by incorporating native species into the landscape. By converting a primarily turf and introduced species landscape into a native landscape with native trees, shrubs, and grasses, there will be a sizeable reduction in emissions from garden equipment. The U.S. Environmental Protection Agency found that the emissions emitted while operating a lawn mower for one hour is equivalent to the pollution caused by driving a car for 20 miles. It was also found that almost 600 million gallons of gasoline are used for lawnmowers each year. Once established, native landscapes need little to no maintenance. Native plants are generally better at removing atmospheric carbon dioxide than turf, most likely because of a more extensive root system accommodating greater water and carbon storage.
As the global population is increasing to greater amounts, the potential for ecological contaminants is staggering. Though some damages done to the environment are irreversible, the decisions we make now and in the future are not. Incorporating native plants into the landscape is an easy approach to contribute to the health of the surrounding environment. In addition to being an aesthetically pleasing method to reduce impact on the environmental, native species in the landscape can also reduce some impact on your pocket book.
Data and statistics provided by U.S. Environmental Protection Agency: www.epa.gov |
