Lawns are prey to more than one hundred different diseases, although they’re not likely to be severe except on bent grass and highly managed lawns. No single chemical can cure all of them, and recommendations change quickly, so consult your local garden center or state agricultural college for the up-to-date recommended remedy. But prevention is favored over treatment. Most lawns are not so easily damaged by diseases if not over-stimulated by high feeding.
Luckily, newer turfgrass varieties have been bred with at least an amount of resistance to diseases. A generation ago almost every bluegrass lawn was victim of excessive leaf spot during spring. Now almost all of the new varieties withstand this disease. A mixture of several varieties should provide you a reasonable disease-proof turf without using fungicidal sprays.
Among the latest innovations in lawn care is the use of endophytes—”contaminated” turf grasses that survive extreme drought conditions better than other grasses and even kill insects. An endophyte can be either bacteria or fungi that live inside another plant without causing disease. These endophytes can be found in broadleaf plants and grasses all over the world. How endophytes work is a mystery, but they’re believed to be fungi that create toxins which disrupt the biology of insects. Plant breeders hope to harness these endophytes (“End-o-fights”) as important tools in bringing down insect population.
The trend toward non-chemical lawns is spreading. In the past, the suburban picture perfect lawn drenched in toxic herbicides and pesticides did more than kill bugs—it made a lot of people sick, primarily because of careless application. Environmentalists, committed gardeners, pest control people, and producers of alternative lawn-care products have shown that organic ideas spread faster than crabgrass. News wire services have carried stories about non-chemical lawns and many writers narrate horror stories experienced by some homeowners. Because of these problems, there has been a boom in sales for oldline organic gardening products.
Presently, about 15% of U.S. households use commercial lawn services that apply pesticides, says the Environmental Protection Agency. It estimates that another 20 to 25% of households are do-it-yourselfers, also employing pesticides on their lawns.
While lawns have many turf diseases, there’s a ray of hope that a lot of these diseases can be checked with systemic fungicides. These are applied to the grass and are absorbed via the root system. At the present time, the composition of fungicides shifts frequently. Hence it is best to consult with your state college of agriculture. The systemics give great control of Sclerotinia dollar spot, fusarium, smut, pink patch, snow mold, and others. Some golf course diseases are checked marginally, if at all, by the systemic fungicides.