On February 2, 2012, the US Environmental Protection Agency approved a section 18 label for Texas for the fungicide Topguard (flutriafol), to control root rot of cotton (CRR) caused by the soil borne fungus, Phymatotrichopsis omnivora. This section 18 is the culmination of several years of research conducted by Dr. Tom Isakeit, Professor and Extension Plant Pathologist, in collaboration with Rick Minzenmayer, IPM agent, as well as other county agents and extension specialists throughout Texas. CRR is the major yield-limiting disease in many of the cotton-production areas of Texas, causing annual losses exceeding $29 million. Yield losses to individual growers vary greatly, but can range up to 100%. Ironically, the severity is greater in years where abundant rainfall would favor high yields of a cotton crop, because the disease increases with higher soil moisture. CRR has been a problem of Texas cotton since the 19th century. The first experiments on control of this disease were published in 1888 and in spite of extensive research efforts since then, there has been no substantial progress, until our recent identification of flutriafol as an effective fungicide. In some of our field trials with strong disease pressure, the yield was increased by as much as 60%. The application is made as a liquid spray to the soil around the seed at planting. Because CRR usually occurs in recurring patches in a field, growers will only need to treat affected portions of the field, rather than the whole field, limiting the amount of this chemical applied to the environment. We are continuing research to improve the efficiency of application, so that less fungicide is needed to manage the disease.