If your St. Augustine grass appears to have been invaded by aliens, you may have a big area. big spots appear as big, dark areas in St. Augustinegrass fields. You can get rid of this fungus infestation and return order to your grass with a little forethought and the right remedy.
What is large patch?
A fungal illness called large patch is produced by a type of the fungus Rhizoctonia solani. This fungi resides in the earth and effects warm-season turfgrass during the changing seasons of spring and autumn. It’s the same illness that causes dark spot in warm-season grass. Large patch was previously known as brown patch until it was recently changed by specialists.
Signs you have large patch
- Circular sections at least one foot in circumference but up to three feet broad
- Patches are yellow, tan/brown, red, or orange
- The grass stalks will readily separate from the plant if you tug on them. This fungi rots the root of the foliage. (Note: Rhizoctonia solani does not affect the roots.)
It’s best to get a formal report before treating these areas on your grass. Before beginning therapy, take a sample of the afflicted region to your Cooperative Extension office for identification.
Conditions that lead to large patch
Almost all mushrooms flourish in moist, humid environments. The following circumstances favor big patches in St. Augustinegrass fields.
- Continuously wet grass
- High humidity
- High nitrogen levels
- Poorly drained soils
- Mowing too low
- High thatch levels
- Excessive shade
The good news is that you have some influence over some of these circumstances.
How to prevent large patch
Proper grass care is the best method to avoid or at least reduce the impact of big patches. In other words, keep doing what you’re doing, but do it properly and at the right moment.
Water: Water your grass before 8 a.m. and only if it shows symptoms of dehydration. Turn on the irrigation when one-third to one-half of the grass appears strained.
Signs it’s time to water:
- Grass turns from green to blue-gray
- Footprints remain on the lawn long after you do
- The earliest leaf blades coil into a V configuration or wilt.
Fertilize: In the autumn and spring, avoid watering the grass. Only add fertilizer in early summer (or late spring) if your soil test suggests it. According to the University of Florida, over-fertilizing the grass with nitrogen (along with overwatering) can result in recurrent fungus breakouts.
Mow: Mowing will not prevent this fungi from assaulting your grass, but it will help keep it from spreading.
Mowing tips:
- Mow your lawn at the appropriate height: 3.5-4 inches for normal varieties and 2-2.5 inches for miniature cultivars.
- trim only when the vegetation is dry, and trim infected regions last (if at all). Gather lawn cuttings from infected regions and cleanse your mower blade between mows. This aids in the prevention of illness transmission.
Dethatch: Consider dethatching if your thatch covering is more than 1 inch thick. Dethatching eliminates extra material from the soil’s surface, allowing oxygen, water, and nutrients to reach the soil’s surface. This should be done in late spring or early summer.
To help break down the extra thatch, you can hire or purchase a liquid biological dethatcher. If you only have a limited space, a hand dethatching brush will suffice.
Aerate: Aeration is a method of opening up packed dirt and allowing more air and water to flow. Aeration devices extract earth blockages, enabling oxygen, water, and minerals to reach the vegetation. As a consequence, the roots are sturdier and healthy, and the grass is more attractive.
How to get rid of large patch
Once the illness has been correctly recognized and your societal practices have been rectified, you can consider whether additional therapies are required. If this is the case, here are some natural and pharmaceutical remedies to explore.
Natural solutions: The main component bacillus amyloliquefaciens strain D747 is sold as an anti-brown patch disease treatment. Because large patch is caused by the same bacterium (albeit a different type), it’s worth a shot on large patch as well. These items can be purchased online or in a neighborhood shop. Most will be marketed as being appropriate for ecological farming.
Chemical solutions: If you had big patch issues in the previous transitory season, it’s best to use prophylactic therapy because you’ll most likely have another epidemic next spring or autumn. In your state, contact your local Extension representative (or check their fact sheets online) to determine the ideal time to administer protective pesticides. When it comes to prophylactic treatments, timeliness is everything, so make sure you get it right.
To prevent your grass from developing a tolerance to pesticides, rotate between two or use a product with more than one active component. Azoxystrobin in combination with propiconazole, pyraclostrobin in combination with triticonazole, and fluoxastrobin are extremely successful against big patches.
A word of caution Because warm-season grasses develop more slowly in the summer seasons, don’t expect fungicides to suddenly restore the lawn’s verdant color. The substances merely keep the fungi from spreading. . The only method to make the grass verdant again is to wait for fresh foliage to develop. (or paint it in the meantime).
FAQ
1. Can dark spots on St. Augustine grass be caused by anything else?
There are numerous other causes of dark patches on your St. Augustine grass.
Maintenance or cultural issues:
–Lack of water
–Herbicide burn
–Scalping the lawn
–Freeze damage
-Too much shadow (it will flatten out and reveal the dirt beneath)
–Excessive wear or foot traffic
–Dormancy
Insects:
–Nematodes
–Chinch bugs
–Mole crickets
–Tropical sod webworms
—Armyworms/grass looper
Other lawn diseases:
–Take-all root rot
–Grey leaf spot
Contact your local Cooperative Extension office, as with any strange illness on your grass, to rule out extraterrestrial attack or other inexplicable reasons.
2. Are some St. Augustine types more prone to big patches?
There are a few St. Augustine varieties that are more prone to big patch than others, according to the University of Florida’s IFAS Extension program. If you’re beginning from fresh and have had problems in the past, avoid selecting a vulnerable variety.
St. Augustine varieties vulnerable to big patch:
—“Raleigh”
—”Captiva” — a miniature variety that is “somewhat susceptible” to overfertilization or overwatering.
—“Delmar” — a dwarf cultivar