Finding source of stress could prevent lawn from browning
In spite of the recent rain, my lawn is getting brown patches all over it. I’ve checked for grubs, but this is something different. Someone told me I might have a fungus. How will I know, and how do I treat it?
When folks call us with questions about their lawns we usually ask them to bring in a sample representative of what is going on. A piece that’s 8 to 12 inches square from the edge of the brown patch, which shows the progression of the problem (part green to part brown) with soil attached is ideal.
Though fungus problems are common, sometimes we discover insect problems such as grubs, cutworms, chinch bugs and, occasionally, even mites.
Having said that, you might have a fungus problem, which is pretty common on lawns in the Grand Valley. It’s important to keep in mind that our disease problems are stress-related problems. The fungus attacks lawns that are weak.
While there are several possibilities as to what brought this on, by far the most common is that of parts of the lawn are not getting enough water. Contrary to what many people think, the fungus is more likely to show up in spots that don’t get as thoroughly watered.
Let me use my own experience as an example. My backyard had several spots that I sprayed with a fungicide. It cleared up and I didn’t give it another thought. Pretty soon, it was back again, so I repeated the process. Well, after doing this off and on for two years — Yeah, I can be a little slow at times! — I thought perhaps I need to look at why those spots were so persistent.
I got my shovel and started sinking it into various places through the backyard without any problem until I got to each of the brown spots. That’s when I discovered they were as hard as a rock. I’d checked the sprinklers and they were hitting those areas just fine, but for some reason, those particular places needed more water than I’d been giving them. I took the hose to them and soaked them really well once a month and haven’t had a problem since.
Now I just know that I need to give those spots some extra water. Once I corrected that problem, the lawn wasn’t stressed and I haven’t seen a sign of fungus since.
Though watering is the most common problem, there are several others that are good to be aware of. I mentioned checking sprinklers and their coverage already.
Thick thatch also can be a problem. The solution then is to aerate your lawn on a regular basis.
If you have a high salt content in your soil, usually only a problem in newer lawns, that can cause all kinds of problems.
Improper mowing is another cause of a stressed lawn. If the grass is allowed to get long and then cut too short, the lawn will protest. Between 2½ and 3 inches is optimum.
It’s also amazing the “stuff” I’ve seen accumulated in the soil under lawns. Mostly, I see things leftover from the original construction site including trash, run-off from rinsed out paint brushes, drywall plaster, chunks of concrete, none of which are visible from above and all of which could cause homeowners to scratch their heads trying to figure out what’s wrong with patches in their lawns.
Sometimes, we just can’t figure out what’s stressing the lawn. If you want to treat it for fungus just to be sure, we have a great fungicide called Fertilome Systemic Fungicide.
You’ll want to spray it twice, 10–14 days apart. Spray those brown patches and the healthy grass around them.
To sum it up, most fungus problems are because of a stressed lawn. Discover the source of its stress, eliminate it and more than likely, your fungus problem will disappear.