Homeowners need to be aware of the brown patch fungus disease attacking lawns. Brown patch disease, which is caused by a fungus, usually attacks lawns during the late fall and early winter time of the year. At this time of the year the conditions are usually right for the fungus to develop and to attack the grasses. Lawns may be especially prone to the disease this year because of being stressed from the early season drought and also because of the recent heavy rainfall from Tropical Storm Lee and cooler temperatures.