Healthy Lawn and Healthy Stormwater

 

Lawns produce significant amounts of nutrient-rich stormwater runoff, and research shows that such runoff can potentially cause eutrophication in streams, lakes, and estuaries (CWP, 1999a, and Schueler, 1995a). Research also suggests that suburban lawns and municipal properties produce more surface runoff than previously thought. (CWP, 1999b). Pesticide runoff (see Pest Control fact sheet) can contaminate drinking water supplies with chemicals toxic to both humans and aquatic organisms. 

Homeowners tend an estimated 40 million acres of turf (Environmental Science and Technology, 2005). If classified as a crop, lawns would rank as the fifth largest in the country on the basis of area after corn, soybeans, wheat, and hay (USDA, 1992). Fertilizers applied to lawns are roughly equivalent to the application rates for row crops (Barth, 1995a). Urban lawns receive an estimated five to seven pounds of pesticides per acre annually (Schueler, 1995b). 

Despite this, few residents consider lawn fertilizer a cause of water quality problems. Less than one-fourth of residents rated it a water quality concern (Syferd, 1995 and Assing, 1994), although that rate rose to 60 percent for residents living close to lakes (Morris and Traxler, 1996 and MCSR, 1997). In one Minnesota survey, only 21 percent of homeowners felt their lawn contributed to water quality problems. Interestingly, more than twice that many felt that their neighbors' lawns did (MCSR,1997). Few suburban and rural landowners are aware of their lawn's nutrient needs. Surveys indicate that only 10 to 20 percent of lawn owners take soil tests to determine if fertilization is even needed (CWP, 1999). Most lawn owners don't know the phosphorus or nitrogen content of the fertilizer they apply (Morris and Traxler, 1996) or that mulching grass clippings into lawns reduces or eliminates the need to fertilize. Helping residents, municipalities, and a lawn care professionals learn methods to reduce fertilizer and pesticide application, water use, and land disturbance can help alleviate the effects of a major source of stormwater pollution in residential communities. 

The public's desire for green lawns is probably the biggest impediment to limiting pollution from this source. Asked their opinion in a Michigan survey about lawns, residents responded most favorably to the statement "a green, attractive lawn is an important asset in a neighborhood" (De Young, 1997). In 2004, America's homeowners spent $36.8 billion on lawn and garden maintenance (Aveni, 1994, De Young, 1997). Convincing residents that a green lawn can be obtained without large amounts of chemicals and fertilizers is difficult when conventional lawn care methods are seen as quicker, more effective and more convenient. 

If you are planning on fertilizing your lawn, be mindful of how your actions will affect your family, pets, lawn and the environment. 

Lawn care, landscaping, and grounds maintenance occur in all parts of the country, in all types of climates, and in every type of community from rural to urban. Lawn fertilization is one of the most widespread watershed practices conducted by homeowners. In one survey of resident attitudes, 89 percent of residents owned a yard, and of these about 50 percent applied fertilizer every year (Swann, 1999). The average rate of fertilization in 10 other resident surveys was even higher, 78 percent, although this could reflect the fact that these surveys were biased toward predominantly suburban neighborhoods, or because they excluded non-lawn owners. Because lawn care, landscaping, and grounds maintenance are such common practices, education programs that teach residents, municipalities, and lawn care professionals to reduce the stormwater impacts of these practices are an excellent way to improve local water quality.

 

Healthy Lawn and Healthy Stormwater

 

To reduce the effects of fertilizer, pesticide and herbicide on receiving waters, lawn care industry workers will first need to be trained and educated about the importance of the maintaining lawns with stormwater in mind. Nationally, seven to 50 percent of consumers use lawn care companies. Lawn care companies exert considerable authority to change homeowner's lawn care practices. For example, in a Florida study (Israel et al., 1995), 94 percent of lawn care companies reported that they had authority to change practices, and that about 60 percent of their customers were at least "somewhat receptive to new ideas." De Young (1997) also found that suburban Michigan residents expressed a high level of trust in their lawn care companies. 

Alternative landscaping techniques such as nature-scaping and xeriscaping can also be used. Xeriscaping is a viable alternative to traditional landscaping. Xeriscaping conserves water and protects the environment by reducing water use (TAMU, 1996). It needn't result in cactus and rock garden landscapes. Rather, cool, green landscapes can be achieved and maintained with water-efficient practices. Xeriscaping incorporates seven basic water-reducing principles (NYDEP, 1997): 

Planning and design. Consider sunlight, soil and drainage conditions; desired maintenance level; which existing plants will remain; plant and color preferences; and budget. 

Soil improvement. Mix peat moss or compost into soil before planting to help the soil retain water. Use terraces and retaining walls to reduce water run-off from sloped yards. 

Appropriate plant selection. Choose low-water-using flowers, trees, shrubs, and groundcovers. Many of these plants need watering only in the first year. 

Practical lawns. Limit the amount of grass area. Plant ground-covers, indigenous plants, or slow-growing, drought tolerant vegetation. If replanting lawns, use drought-tolerant grass seed mixes.

Efficient irrigation. Install water-efficient drip or trickle irrigation systems. 

Effective use of mulches. Use a 3-inch deep layer of mulch, such as pine needles, shredded leaves, or bark. Mulch keeps soil moist, prevents erosion, and smothers weeds. 

Appropriate maintenance. Properly timed fertilizing, weeding, pest control, and pruning preserve a landscape's beauty and water efficiency. 

Naturescaping returns native plants and wildlife habitat to your yard or community. Naturescaping conserves water and energy, reduces water and soil pollution, and creates wildlife habitat. The practice is founded on the use of native plants that are naturally resistant to local pests and diseases. Once established, native plants can often survive on rainwater alone. Naturescaping areas can be created by replanting a section of lawn with a wildflower meadow, a hummingbird and butterfly garden, or plants and trees selected for seeds, fruit, and nectar, and nesting boxes. 

When creating a naturescape, it is important to include four elements: food, water, shelter, and adequate space. Keep the following steps in mind when creating a naturescape in your yard or community: 

Visit "wild" places and naturescaped sites and imagine how these landscapes would fit in your yard or community. 

Educate yourself and your community. Learn about native plants and basic design and care concepts. Attend workshops, and read plant and design books. 

When you are ready to develop a site plan, choose a small, viewable site. When planning, consider maintenance, water, gardening, and feeder access. Know the existing conditions of the area shade/sun, wet/dry, wind patterns, drainage, existing plants and animals. Once you develop a plan and you have obtained any necessary permits, you are ready to gather your material and begin. 

Integrated Pest Management (IPM) is an effective and environmentally sensitive approach to pest management. It relies on a combination of common-sense practices. IPM programs use current, comprehensive information on the life cycles of pests and their interaction with the environment. This information, in combination with available pest control methods, helps manage pest damage by the most economical means, with the least possible hazard to people, property, and the environment. 

The IPM approach can be applied to both agricultural and nonagricultural settings, such as the home, garden, and workplace. IPM takes advantage of all appropriate pest management options, including but not limited to the judicious use of pesticides. In contrast, organic food production applies many of the same concepts as IPM but limits the use of pesticides to those that are produced from natural sources.

IPM is not a single pest control method. Rather, it is a series of pest management evaluations, decisions, and controls. Integrated pest management is a sustainable approach to managing pests, combining biological, cultural, physical, and chemical tools. Municipalities can encourage homeowners to practice IPM and train/encourage municipal maintenance crews to use these techniques for managing public green areas. There are many methods and types of integrated pest management, including the following: 

Mulching helps prevent weeds where turf is absent. Fencing helps keep out rodents. Netting helps keep out birds and insects away from fruit and leaves. 

Insects can be removed by hand (using gloves or tweezers) and placed in soapy water or vegetable oil. Alternatively, insects can be sprayed off the plant with water or in some cases vacuumed off of larger plants. 

Store-bought traps can be used, such as species-specific, pheromone-based traps or colored sticky cards. 

Sprinkling the ground with abrasive diatomaceous earth can prevent infestations of soft-bodied insects and slugs. Slugs also can be trapped in small cups filled with beer set in the ground. 

In cases where bacteria, fungi or other microscopic organisms are damaging plants, the affected plant material can be removed and disposed of. (Pruning equipment should be disinfected with bleach to prevent spreading disease organisms.) 

Small mammals and birds can be excluded using fences, netting, tree trunk guards. 

Beneficial organisms like bats, birds, green lacewings, ladybugs, praying mantis, ground beetles, parasitic nematodes, trichogramma wasps, seedhead weevils, and spiders can be promoted.

 

Additional Tips:

 

Never over fertilize. Always follow the directions on the label to make sure you are not using too much fertilizer for your lawn. Aside from the fact that chemical fertilizers are unsafe for your family and pets, excess fertilization weakens roots, increases watering needs, causes thatch and excessive growth, and pollutes waterways. Remember, twice as much will not do twice the job. 

Check the weather. Fertilizing shortly before a rainstorm results in the fertilizer washing off of your lawn, making the application ineffective for its intended purpose. In addition to wasting your money, the rain carries the fertilizer to waterways via storm drains. Once in our waterways, the fertilizer stimulates excessive algae and plant growth which can result in fish kills. 

If you must fertilize, September is the best month. And be sure to use slow-release fertilizer.

If you want to fertilize more than once, don’t fertilize in the spring until you have mowed the lawn three times. 

More is not always better! Skip the “step programs” offered by many lawn care companies, and be sure to apply fertilizers and pesticides only as directed. Using less will save you money, too! If you do use a lawn care company, ask them about their environmental options and certifications.

Go natural: mow high and leave grass clippings on the lawn. It helps improve the lawn’s health and quality, and you’re less likely to need fertilizer.

Avoid using fertilizers or pesticides near wellheads or within 75 feet of waterways.

Avoid using combination fertilizer/pesticide products. Hand pick weeds when possible, and if you must treat weeds or insects with pesticides, spot treat them rather than dousing the entire lawn.

Use chemical pesticides as a last resort. Pesticides can kill species that benefit the environment, as well as your target species. 

Pesticides may poison children and pets. Try non-toxic alternatives or use a lawn care service that offers such treatments.

Store or dispose of leftover chemicals properly, not in the trash. 

NEVER dump anything down the storm drain. 

One great alternative to synthetic fertilizers is “grasscycling” or leaving grass clippings on the lawn to decompose into the soil. Many people have found that grasscycling greatly reduces or completely eliminates the need for synthetic lawn fertilizers. Consequently, grasscycling can benefit your pocketbook, your lawn and your environment. 

For additional information, visit www.epa.gov/pesticides/controlling/garden.htm.