ST AUGUSTINE is a warm-season turf that remains vulnerable to common lawn diseases. These infections are rampant primarily during the summer and spring growing periods. Generally, these diseases can negatively impact your lawn, leading to an unsightly property. Here are the five common St Augustine grass diseases.
The common St Augustine grass diseases include take-all root rot, gray leaf spot, brown patch, fairy ring, and nigrospora stolon rot. All these can negatively impact your St Augustine lawn if not controlled quickly. To know your grass is infected, check for symptoms like yellowing, browning, or thinning of grass blades. Watering your grass adequately and frequent fungicide application helps significantly in controlling these diseases.
What Are the Symptoms of St Augustine Grass Disease?
There are various ways to tell that your St Augustine grass is infected with lawn diseases. As you can see in the above St Augustine grass diseases pictures, some infected grass blades appear yellow. In some areas, you can see dark green circles of turf enclosed by a ring of dead grass.
Also, the infested leaves appear chlorotic, thin, and less vigorous. Additionally, from the above pictures of St Augustine grass diseases, the irregular brown patches on the lawn are evident. This means the turf is thinning out and dying in spots due to these lawn diseases.
What Common Diseases for St Augustine Grass?
St Augustine grass disease identification is vital before applying just any fungicide. Here are the most common diseases you can find on this lawn and their identification;
1. Take-all root rot (TARR)
This St Augustine grass disease is caused by over-watering, under-watering, excessive shade, and extreme temperatures. It attacks the grass root system, causing rotting of roots. You can identify it by small patches with weird shapes.
2. Gray leaf spot
Gray leaf spot is another lawn disease that affects St Augustine grass leaves. It is caused by Pyricularia grisea and thrives in shaded lawns and those with warm temperatures and abundant moisture. You have gray leaf spot disease in your yard if you see oval or round spots surrounded by dark brown borders.
3. Brown patch
Another common disease in St Augustine lawns is brown patch. It is caused by excessive fertilizer application, thatch, and soil moisture. When it attacks, the infected leaf blades thin out, develop dark brown patches, and fall loose easily.
4. Fairy ring
This lawn disease thrives in sandy soils with less nitrogen and excess thatch. Once it attacks, it leaves your property with dark green circles of turf enclosed by a ring of dead grass.
5. Nigrospora stolon rot
Nigrospora stolon rot is a St Augustine grass disease prevalent during the dry summer and spring seasons. Its symptoms include dark brown lesions on stolons and thinning and yellowing of new grass.
Frequently Asked Questions (FAQs)
Q: Is St Augustine Floratam grass susceptible to any diseases?
A: Floratam St Augustine grass is extremely susceptible to Lethal Viral Necrosis (LVN). Sugarcane Mosaic Virus causes the disease, and once it infects your Floratam lawn, it kills it within three years.
Q: What is the best fungus treatment for St Augustine grass?
A: The recommended fungicides for treating St Augustine grass are mycobutanil, propiconazole, azoxystrobin, and thiophanate methyl. They are available in the market as bottled products. To apply them on your lawn, attach the bottle to the garden hose and spray on your property.
Final Word
St Augustine grass remains susceptible to various lawn diseases under certain conditions. These diseases include take-all root rot, gray leaf spot, brown patch, fairy ring, and nigrospora stolon rot. Once they attack your St Augustine lawn, they cause symptoms like yellowing, browning, or thinning of grass blades. The best way to control these diseases is by watering your grass adequately and applying fungicides frequently.