Photo – large patch symptoms in spring
We humans are enjoying the cool weather, and our cool-season grasses are too. However we are coming up on the time when our warm-season grasses start to shut down, and the season when the large patch pathogen likes to infect our zoysia. Sometimes we see symptoms in fall if conditions are very cool and wet. I have not seen any around here yet, but in Missouri some is firing. Our main time of seeing the symptoms is spring.
In Kansas, applications in September have been quite effective in reducing symptoms through most or all of the following spring. With this early cool weather, leaning towards earlier rather than later in the month may be wise. Next door in Missouri they’ve seen good results with EARLY spring applications as well – read about it HERE in Dr. Miller’s excellent post about application timing. In Kansas, when we’ve tried mid/late spring applications when symptoms are already pretty apparent, they don’t work well, if at all. For details on the newest products you can check the large patch section here (click to page 18)
http://www2.ca.uky.edu/agcomm/pubs/ppa/ppa1/ppa1.pdf
Here is a video with some descriptions of the biology and symptoms:
