Which factor is associated with the occurrence of large patch in turf?

The occurrence of large patch in turf, particularly in warm-season grasses like zoysiagrass and bermudagrass, is closely associated with high nitrogen levels, especially when applied in the fall and spring. This condition typically arises as the fungus Rhizoctonia solani thrives in environments that have excessive nitrogen. When nitrogen levels are elevated, it can lead to lush, vigorous growth of the turf, which in turn makes it more susceptible to disease outbreaks, including large patch.

Practices like excessive nitrogen application promote a growth condition that can weaken plant defenses, making it easier for pathogens to establish and spread. Therefore, understanding the timing and levels of nitrogen applied to your grass during these critical growth phases is essential for managing the health of the turf and avoiding large patch occurrences.

In contrast, low mowing height may stress the turf and detract from its health, dry soil conditions can lead to other issues such as drought stress and may not be directly linked to large patch, while frequent irrigation could lead to waterlogged conditions promoting other types of disease rather than emphasizing the nitrogen-disease relationship central to large patch.