surrounding environment, inform laws constraining their use. For example, the Canadian province of Quebec and over 130 municipalities prohibit the use of synthetic lawn pesticides. The Ontario provincial government promised on 24–2 September 2007 to also implement a province-wide ban on the cosmetic use of lawn pesticides, for protecting the public. Medical and environmental groups support such a ban. On 22 April 2008, the Provincial Government of Ontario announced that it will pass legislation that will prohibit, province-wide, the cosmetic use and sale of lawn and garden pesticides. The Ontario legislation would also echo Massachusetts law requiring pesticide manufacturers to reduce the toxins they use in production. Experts advise that a healthy lawn contains at least some "weeds" and insects, discouraging indiscriminate use of potentially harmful chemicals. Sustainable gardening uses organic horticulture methods, such as organic fertilizers, biological pest control, beneficial insects, and companion planting, among other methods, to sustain an attractive lawn in a safe garden. An example of an organic herbicide is corn gluten meal, which releases an 'organic dipeptide' into the soil to inhibit root formation of germinating weed seeds. An example of an organic alternative to insecticide use is applying beneficial nematodes to combat soil-dwelling grubs, such as the larvae of chafer beetles. The Integrated Pest Management approach is a coordinated low impact approach. Mowing and other maintenance practices Maintaining a rough lawn requires only occasional cutting with a suitable machine, or grazing by animals. Maintaining a smooth and closely cut lawn, be it for aesthetic or practical reasons or because social pressure from neighbors and local municipal ordinances requires it, necessitates more organized and regular treatments. Usually once a week is adequate for maintaining a lawn in most climates. However, in the hot and rainy seasons of regions contained in hardiness zones greater than 8, lawns may need to be maintained up to two times a week. Social impacts The prevalence of the lawns in films such as Pleasantville (1998) and Edward Scissorhands (1990) alludes to the importance of the lawn as a social mechanism that gives great importance to visual representation of the American suburb as well as its practised culture. It is implied that a neighbor whose lawn is not in pristine condition is morally corrupt, emphasizing the role a well-kept lawn plays in neighborly and community relationships. In both of these films, green space surrounding a house in the suburbs becomes an