What seasonal factor can lead to higher occurrences of brown patch?

The occurrence of brown patch, which is a common lawn disease caused by the fungus Rhizoctonia solani, is significantly influenced by environmental conditions. The correct choice, overcast and humid conditions, fosters the development of this disease because the fungus thrives in warm, moist environments. High humidity creates a suitable atmosphere for the fungal spores to germinate and spread, while lower light conditions can stress the grass, making it more susceptible to infections.

When grass remains damp for extended periods, as is common in overcast and humid weather, it creates ideal conditions for fungal growth. The spores not only survive better but also can spread more effectively, leading to a higher occurrence of brown patch in those lawns that experience such environmental factors.

In contrast, cold weather does not promote brown patch since the fungus generally prefers warmer conditions. High winds can dry out grass and reduce humidity levels, both of which hinder the development of the disease. Low humidity tends to create an environment where the grass remains drier, again making it less susceptible to fungal infections like brown patch.