Managing Turfgrass Diseases
Turfgrass Disease Development
There are several diseases that could potentially infect turf
in northern Illinois. The general environmental conditions occurring
on the turf, how the turf is managed, and weather conditions all
impact turfgrass disease development. Turf diseases need favorable
conditions to develop. The best defense against diseases is to
maintain healthy turf through sound cultural practices, avoiding
favorable conditions for disease. Disease outbreaks often occur
when turfgrasses are not managed properly or are under extreme
stress, such as from poor soil conditions or perhaps weather conditions
(see Table 1).
Table 1: Disease Requirements & Turf Disease Management
||Management Practices to Avoid Disease
|Susceptible Grass Plant
Use of mixtures/blends
(Fungi for most diseases)
|Fungicides (temporary protection)
Can never eliminate all causal agents
|Proper Environment for
Causal Agent to Develop
Proper turf management practices
(watering, fertilizing, etc.)
Fungicides are rarely suggested for use on home lawns. Instead,
follow sound lawn care practices to prevent serious problems.
When a disease outbreak occurs, follow renovation procedures and
adjust future lawn care practices as needed to prevent the disease
Some Common Turfgrass Disease Scenarios
Low Fertiliy, Moisture, Turf Vigor
||Small blighted areas.
Hourglass lesion girdles blade. Colored band on lesion edge.
||Pink to red masses on leaf blades.
Threadlike appendages from leaf tips.
Orange pustules on leaf blades.
Orange powder from affected grass.
Excess Nitrogen Fertility, Thatch
||Brown to purple lesions (spots) on blades.
Irregular dying areas of grass.
Lesions on grass in margins of dead areas.
||Irregular matted areas.
"Moldy" appearance in spring.
Heavy Clay Soil, Soil Compaction, Thatch,
Necrotic Ring Spot
|Circular/crescent shaped patches.
Irregular dead areas.
Patches in newer sodded lawns.
Written by Bruce Spangenberg, former Extension
Educator, Horticulture. University of Illinois Extension.