The Future of Lawn Care in Virginia

About half of the land area of Virginia is drained by the creeks, streams and rivers that comprise the Chesapeake Bay watershed, and two-thirds of the state's population lives within the watershed. From the Shenandoah Valley to the Eastern Shore, each Virginian can literally touch the Chesapeake Bay through the network of creeks and streams that cover the area. In an effort to reduce pollution in urban and suburban runoff one of the growing areas of nutrient pollution in the Chesapeake Bay estuary, the 2011 Virginia General Assembly passed SB 1831 that bans phosphorus in most lawn fertilizers and more tightly restricts the use of fertilizer by professional lawn and turf service companies. This bill was supported by the Chesapeake Bay Foundation and the Piedmont Environmental Counsel.

The newly passed law prohibits the sale, distribution and use of lawn maintenance fertilizer containing phosphorus after December 31, 2013 and it will be unlawful to offer for sale any deicing agent containing urea, nitrogen, or phosphorus intended for application on parking lots roadways, and sidewalks, or other paved surfaces. The law also requires golf courses to implement nutrient management plans by July 1, 2017, and will utilize the existing resources of the Soil and Water Conservation Districts and the Department of Conservation and Recreations to provide technical assistance and training and establish a cost-share program to assist in implementation of the nutrient management plans. For homeowners the Department of Agriculture and Consumer Services will develop consumer information and recommended best practices for the application of lawn fertilizer. The law also regulates lawn service companies and establishers reporting requirements for those who apply lawn fertilizer to more than 100 acres of nonagricultural lands annually This effectively leverages the existing resources and expertise to get the most bang for the buck in meeting the Chesapeake Bay TMDL and restoring the Chesapeake Bay estuary and should not impact property owners excessively. Research has shown that most lawns are not deficient in phosphorus and phosphorus free lawn fertilizer is widely available.

The TMDLs were created by a series of models of the Chesapeake Bay Watershed that include various land use models, water quality models and watershed models. These computer models are mathematical representations of the real world that estimate environmental events and conditions. The models are at best imperfect, but they are nonetheless the best tool available to view the 64,000 square miles of the watershed. The Chesapeake Bay and its watershed are so large and complex, that scientists and regulators rely on computer models for critical information about the ecosystem’s characteristics and the impact of various environmental actions to reduce pollution.

Pollutions loads for nitrogen, phosphorus and sediment in the urban areas are calculated using a constant pounds/acre/year for impervious acres as a fixed input, and the pervious load is based on total fertilizer sales data. Reducing the salting of roads, sidewalks and parking lots should impact the load number on impervious acres. Restricting the statewide sales of phosphorus containing fertilizer will reduce the total sales number which represents roughly five percent of excess nitrogen and phosphorus pollution discharged into the Chesapeake Bay from Virginia.

Most lawns are not deficient in phosphorus. Despite the widely accepted myth that phosphate fertilizers will stimulate root growth of transplanted trees and shrubs, research at Washington University has proved this incorrect. Only soils that have been heavily used for agricultural crops or are acid sandy and granitic soils tend to have their phosphorus depleted. In landscaped urban soils, phosphorus is rarely deficient and the misapplication of this element can have negative impacts on the soil environment and the watershed without any benefit to the lawn or plants. Restricting the statewide sale of lawn fertilizer containing phosphorus and educating homeowners about the inappropriate use of lawn fertilizers is a simple way to reduce nitrogen and phosphorus runoff and save consumers a few dollars on unnecessary fertilizer. This could prevent the EPA from implementing stricter stormwater point source limits which was one of “backstop” threats leveled at Virginia if we fail to meet the Chesapeake Bay TMDL goals. This simple step should be all the more effective when the suburban/urban surface portion of the Chesapeake Bay model is revised.

Pesticides and Ornamental Gardens

On Thursday, July 30th the Wall Street Journal published an article by Gwendolyn Bounds entitled “Death by Mint Oil: Natural Pesticides.” As Ms Bounds points out more and more pesticides, herbicides and insecticides derived from naturally occurring substances are now commercially available. Some of the more natural pesticides were introduced in the 19th century, and are based on, pyrethrum which is derived from chrysanthemums, and rotenone which is derived from the roots of tropical vegetables. Others like boric acid (used to kill amongst other pests termite colony invasion inside homes and ant hills) and soap salts are just older and though modesty less effective are believed to be far less toxic. These older, naturally occurring chemicals are a step back, but believed to be even safer than the new generation of herbicides developed during last quarter century encouraged by the US EPA. Those newer herbicides were applied at much lower levels, broke down more quickly in the environment and were less toxic to animals. The new generation of herbicides was based on sulfonylurea and imidazolinone. Now it seems that the degradation products of these new herbicides are far more persistent in the environment that originally believed or hoped and we are looking once more at older, natural solutions.

Pesticide' is a broad term, covering a range of products that are used to control pests. The slug pellets, ant powder, weed killers, and rat and mouse baits that you may use in your everyday life are all pesticides. Other pesticides you may have heard of including: insect killers (insecticides), mould and fungi killers (fungicides), weed killers (herbicides), slug pellets (molluscicides), plant growth regulators, bird and animal repellents, and rat and mouse killers (rodenticides). Often people only think of pesticides as chemicals, but they include a very large range of different types of products. Some as described above are natural, while many are altered versions of natural chemicals.

In Canada there is a growing movement to ban the use of pesticides for ornamental use. Town by town, Provence by Provence bans are appearing. Ontario and Quebec have banned the pesticides use for cosmetic purposes on lawns, vegetable and ornamental gardens, patios, driveways, cemeteries, and in parks and school yards. There are no exceptions for pest infestations (insects, fungi or weeds) in these areas, as lower risk pesticides, biopesticides and alternatives to pesticides exist. More than 250 pesticide products are banned for sale and over 95 pesticide ingredients are banned for cosmetic uses. Pesticides, including herbicides, insecticides, fungicides, and rodenticides, used to simply prevent blemishes and other imperfections on private and public lands are referred to as the cosmetic (or ornamental) use of pesticides in these regulations. The question is should we be following the Canadian lead in this?

Though there has been no direct evidence linking pesticides with the exception of nitrogen to diseases in humans, an increasing number of health and environmental groups are claiming that these chemicals do indeed impact human health. A wide range of chemicals are used to treat everything from pests to mold in household gardens. One of those is 2, 4-D, used by cereal crop producers and commonly found in household weed killers. It has been the subject of an extensive study by Health Canada which determined that, when used properly, it is safe. Organizations like the Sierra Club and the Canadian Cancer Society, which strongly support a ban on cosmetic use of pesticides and herbicides, disagree. However, no specific research linking the currently used ornamental pesticides to disease in humans was found.

The only documented study to find a disease link to 2,4-D was done in the United States, a 1991 National Cancer Institute study examined dogs whose owners' lawns were treated with 2,4-D four or more times per year. The study found those dogs had double the risk of developing canine malignant lymphoma than dogs whose owners do not use the herbicide. Overall, it appears that the Canadian ban on cosmetic use of herbicides and pesticides is based on an emotional and logical belief that cchildren may be more at risk of developing health problems from pesticides because:

• Their activities lead to more exposure e.g., playing in the grass, putting their hands or toys in their mouths.
• They are closer to the ground and breathe in higher amounts of pesticides.
• Proportional to their weight, they breathe in more air and consume more food and drink than do adults.
• Their immature metabolic systems cannot break down toxins as effectively as adults.
• Their bodies are rapidly growing and developing and potentially impacted more strongly by endocrine disruptor effects.

While I certainly do not know if a ban on ornamental use of pesticides will prevent disease in children, I wonder what the downside of reducing use would be. (For full disclosure purposes I have the third to worst lawn in my neighborhood, I apply no chemicals to my lawn and never water. However, I do hope to improve the lawn by aerating and over seeding annually and applying my compost. So far, not so good despite soil analysis that showed decent soil composition.)