You Are Here: Management Updates 2000 Archive September 28, 2000

Date: September 28, 2000
Category: Diseases
Subject: Rust

The heavy fogs and rainy weather are very conducive to rust this year in golf course roughs and lawns and grounds throughout New England. Rust is easily diagnosed by observing the tiny pustules of orange (rust) powdery spores. Older infections may also develop pustules of black spores. The leaf blades will turn yellow. Fast growing turf that is mowed regularly usually doesn't develop this problem because it takes 10-14 days for spores to develop. Turf that is slow-growing because of low N, compaction, dry soil, etc. is most likely to develop rust. At the other end of the management spectrum, high N and prolonged leaf moisture can favor rust if the turf is not mowed off quickly. The disease is not usually too damaging, and the orange spores will die over the winter. In severe cases, DMI (sterol-inhibitor)-type fungicides such as propiconazole and triadimefon are very effective. Most contact fungicides are not very effective and must be reapplied frequently. Fungicides are not usually necessary.

- Submitted by: Dr. Gail Schumann