Grow What Belongs Here
Sure, it's pleasant to sit out on your back deck on a warm summer night and look over your own half-acre carpet of weed-free, perfectly groomed grass. And, yes, it's delightful to walk among the flowerbeds decked out with fragrant, brilliant, bugless rose bushes. But what is the cost to the community's health and environment to apply the sprinkles of fertilizer, the douses of pesticides, to bring your own landscape into such tidy control? Too high, say many of those concerned about the toxic levels of pesticide residues found in the nation's rivers and streams. Plenty of the chemicals used in garden applications are considered to be carcinogenic, neurotoxins or hormone disrupters, and therefore harmful to humans, fish and other wildlife. For instance, a 1997 U.S. Geological Survey study of the water in the Willamette River found high percentages of a number of chemicals such as the pesticide Diazinon; the commercial chemical Atrazine, used in pesticides and linked to breast cancer and hormonal problems; and Simazine, an herbicide linked to breast cancer and male fertility problems that is particularly toxic to sheep and cattle.The government is also concerned that the country's children are the ones being most hurt by the unchecked use of garden chemicals. Current EPA benchmarks for safe daily exposure to pesticides are based on adult exposure. Under a mandate of the 1996 Food Quality Protection Act, the EPA must develop new exposure standards for infant and child exposure. While there is no clear prediction of what the EPA's recommendations will be -- many won't come out until 1999 -- EPA pesticides expert Karl Arne predicted in a recent interview that more conservative health requirements could translate to restricted use or all-out banning of some of the insecticides. In its review, the EPA is studying organophosphates, insecticides originally derived from the Auschwitz nerve gas phosgene, according to literature from the Northwest Coalition for Alternatives to Pesticides. "Like lead, organophosphates can cause long-term, yet subtle damage to the brain and nervous system, especially when young children are exposed," according to NCAP.Furthermore, the Environmental Working Group released a report in January on the current level of exposure for American children, and found that "every day, nine out of 10 American children between the ages of 6 months and five years are exposed to combinations of 13 different neurotoxic insecticides in the foods they eat."Pesticides don't have to be organophosphates to be toxic, of course. They are poisons by nature: Three-quarters of a cup of Roundup weed remover, for instance, is a fatal adult dose, according to NCAP.Joanne Wolfe, editor of the new native gardening magazine Wild Garden, said that the chemical Diazinon is only one of many deadly pesticides people use in their gardens and on their lawns. There's also Diuron, and Weed and Feed. "These chemicals are dangerous, and people let their dogs and their children play in them," she said.The uncertain health effects of pesticides and the dependent nature of "exotic" (non-indigenous) vegetation on fertilizers and extra water all make a strong case for using native plants in your garden, Wolfe said. According to Harold Greer, owner of Greer's Gardens in Eugene, native options for gardening are fairly extensive, and include flowering plants such as wax myrtle, which has laurel-like flowers; the local currant Ribes canguiheum, which has drooping clusters of bell-like flowers; and kinnikinnick, a hearty plant with small round leaves. "When you purchase exotic plants and put them in your garden, you are not creating a sustainable landscape," Wolfe said. "The garden can't sustain the natural wildlife because it hasn't evolved with the climate here -- you are essentially creating a landscape that doesn't function. It may be pretty, but it's sterile," Wolfe said.Because of the inherently frail nature of exotic plants, urban gardeners depend on large amounts of pesticides and fertilizers to sustain them, Wolfe said. "There are more chemicals used on typical home lands than on agricultural crops."But gardeners who choose indigenous plants can avoid pesticide dependency altogether. "When you purchase natives, you start to create a community. The plants and the local wildlife help each other; the birds bring in new seeds and so on. Rather than you being in control, the garden lives," Wolfe said.Natives are also naturally adjusted to the local climate, so they don't depend on extra water or fertilizers to survive, Wolfe said. According to Greer, many native species need watering while they are new to a garden, but in time require less and less. He also cautioned that not all indigenous plants adapt easily. For example, the native rhododendron growing in the Cascades depends on glacial flow, which makes this plant dependent on low-temperature soil -- a condition that doesn't transfer well to the valley. Native vegetation can also push out noxious weeds, alleviating some of the need for herbicides. Blackberries, unfortunately, are heartier than nearly all the Willamette Valley natives, Greer said, but strong ground-covering plants such as salal and kinnikinnick can crowd out some weeds. With a native garden, "the whole point is to recreate habitat that is self-sustaining," Wolfe said. "It is critical to maintain native seeds and to plant natives -- when we don't, we're messing with the entire web of life. Pesticides affect the air, water and local creatures. Natives keep our habitat viable and sustainable."