(South Alabama) We have been trying to kill weeds and regrow our grass. We put pre-emergent down and spread some grass seed- we’ve also been spreading fertilizer. Pictures for reference: we cannot figure out why there’s these rings of dead grass on our lawn. Any ideas to why and any suggestions to fix it?
by TouchWild1115
8 Comments
https://preview.redd.it/8s71xsgfo60h1.jpeg?width=1320&format=pjpg&auto=webp&s=f901901d35148a3e0a548fcfcb1c9baf2bd7d183
Use one these from your local HomeDepot or Lowes to break up the bare spots. Put some top soil and seeds. Water twice a day in before sunrise and before sunset.
Just needs a tilling and a fluff up, and a quick re-seed.
Looks like large patch. Rhizoctonia solani.
Edit: Chlorothalonil (commonly sold as Daconil) will clean than up. Might take a little while for the grass to heal out of it. Don’t add any nitrogen fertilizer until the disease has been knocked out or you’ll exacerbate it.
Not enough disco lights
There’s a fungus among us! Daconil is a great option to clear that up, don’t do anything else until it’s gone.
How long did you wait after pre-emergent to spread seed? Also what seed did you spread? Grasses that thrive in South Alabama generally don’t grow well or at all from seed.
You have the dreaded ***fairy ring!!!*** It is a big fungus and it probably grows outward about 6″-18″/year and a ring that size probably goes down 6″-18″ deep.You may see mushrooms pop up in that dead patch, and you may see very bright green grass on both sides of the dead patch. The grass inside the circle has recovered while the grass just outside the ring will probably die in the future. Fairy ring kills your grass two ways:
1. As the fungus grows, it breaks down organics in the soil into notrogen components and essentially kills the grass with over-fertilizarion (e.g. ammonium toxicity). Normally you combat this by wtering to dilute and wash away the excess nitrogen.
2. However, the fungus creates a hydrophobic (repels water) “mat” which prevents water from diluting and removing the excess nitrogen.
Correcting your watering habits is the most effective prevention and you might never know it is there; it also become less visible on its own due to seasons. Killing it is a multi-year effort, or you dig it out (~24″ down and 3′ wider than the visible ring); both are a pain in the ass and expensive.
Treatment to just manage it is less impactful to the wallet:
1. Aerate the crap out of the area (ring +/- 3′). Deep-tine (~6″ holes everywhere) to penetrate that hydrophobic mat. This creates a physical path to get water into the soil.
2. After aeration, hand water with 1 tsp dawn dish soap (surfactant) per gallon of water. The dish soap will break the surface energy and help the water penetrate to get to the roots and wash away some of the nitrogen.
3. After those steps, water, water, then water. You are diluting and washing away the nitrogen to get it to healthy levels.
Honestly, the suggestion of the cultivator, some new soil, and reseeding isn’t a bad way to make it look better for a while. But, the fungus will eventually recolonize that soil.
I would check with your local extension office before trying any fungicides. They are really expensive and are worthless unless you use them exactly per label combined with the aeration and surfactants (otherwise they don’t get to the fungus and get washed away). Treatment this easy takes several years to stop the recurrence of the ring.
Oh great, a sub dedicated to the most useless invasive plant in North America. God I hate you people.
Not enough grass