Diagnosing lawn diseases is not easy. Many diseases have similar symptoms and symptoms vary with the
progress of the disease. The following are some general clues that can help you make the call.
Plant Symptoms
|
Cause
|
Fungal growth on the blade |
Long black streaks of powdery spores |
Stripe smut |
Powdery white dust |
Powdery mildew |
Red / Orange powder |
Rust |
Gray fungus that is easily rubbed off |
Slime mold |
Spots on leaves but no fungus visible |
Reddish brown to blue-black, circular or oval |
Leaf spot |
Straw-colored bands with a reddish brown border |
Dollar spot |
Lawn Symptoms
|
Cause
|
| Circular diseases areas |
| Observed in late winter or early spring |
Snow mold |
| Present in summer, spring or fall (1" — 4' or more in diameter) |
|
With mushrooms
|
Fairy ring |
No mushrooms
|
Brown patch |
| Present in summer, spring or fall (1" — 8" in diameter) |
|
Throughout the lawn
|
Dollar spot |
Only in full sun, show green center
|
Fusarium blight |
In low areas and often in streaks
|
Pythium blight |
| Irregularly shaped diseased areas |
|
New lawn seedlings wilt and die
|
Damping-off |
Mature lawn affected, spots on leaves
|
Leaf spot |
If diseases do strike your lawn, you can deal with them individually once you are able to recognize
their signs. It is important to first know the disease before beginning to make arbitrary treatments.
