yellowish brown spots in st augustine lawn

btg · Joined: 08 Jul 2006 Posts: 6 Location: crowley,TEXAS

i live in ft worth and recently sodded my back yard because it died. the new sod has been in since april and has become very lush. it gets direct sun and i water regularly 2-3 times per week. recently however, i have noticed patches where the grass is turning brown underneath the new growth. this is how my lawn started to disintegrate last year. i just fertilized with corn gluten meal and seaweed minerals in water form. any ideas what this condition is, do i need to be concerned and if so, what do i need to do to treat? prior to the new sod, i put down a grub worm insecticide and again on top after completion of the installation. lawn is growing nicely and is very thick. i cut on the highest setting twice a week and mulch back into the soil. :?:

khwoz · Joined: 10 May 2003 Posts: 778 Location: Weatherford,TX

My first guess would be - Too much water. You should only have to water once a week deeply. The excess water will cause the fungal conditions you describe. Spread some horticultural cornmeal & cut back on watering. If the grub insecticide was a chemical, that didn't help matters either. In the future use beneficial nematodes to control lawn bugs. Keep in mind that most types of grubs are beneficial.

btg · Joined: 08 Jul 2006 Posts: 6 Location: crowley,TEXAS

khwoz: thanks for the information, i thought this might be a reason as well. spots appear to be dissipating. i used CGM & seaweed minerals. will this make the lawn greener as well? do you have some suggestions that would really enhance the green quality of the lawn? appreciate it.

khwoz · Joined: 10 May 2003 Posts: 778 Location: Weatherford,TX

The corn gluten meal is a good fertilizer (somewhat expensive). I would use it at the proper time of year as a pre-emergent. That way you get a double benefit. A good, fine compost works wonders as do most other amendments (lava sand, green sand, compost tea, etc.) If you want to find out what your soil is lacking, have a soil test done. The following is from Howard.

Soil Testing
Have soil tested, by a lab that gives organic recommendations, to learn the total and available levels of organic matter, nitrogen, calcium, magnesium, sulfur, phosphate, potassium, sodium, chloride, boron, iron, manganese, copper and zinc. Tissue sample tests are important to see what nutrients are being taken up by the plants. Check for life by counting the earthworms in a square foot of soil - should be at least ten. The best lab for organic recommendations is Texas Plant and Soil Lab in Edinburg Texas. They may be reached at 956-383-0739.

There is a lot of info on this discussion board & the web site. Do some searches & you can evaluate different peoples ideas and approaches to yard care.

btg · Joined: 08 Jul 2006 Posts: 6 Location: crowley,TEXAS

KHWOZ: thanks for your advice, i haven't watered as much an it seems as if the yellow spots are slowly dissipating. I have a lot of a blue green type of grass that is growing in the yard and it wasn't there last year. How can i get rid it short of attempting to pull it up. I also used CGM on the lawn and it did nothing to green it up, in fact, the front has turned somewhat lime green in color. what is the best product or products to use for greening and this unknown grass in my lawn? what does the Garrett juice do and what about molasses? where do i get this tea product i hear people talking about? lots of questions, point me in the right direction. i appreciate it. btg

khwoz · Joined: 10 May 2003 Posts: 778 Location: Weatherford,TX

Let me add to the watering suggestion I gave earlier; with all this heat & no rain, you may need to water more often than weekly - maybe every 5 days. The main thing is to water deeply. Personally I have never worried about other grasses growing with St. Augustine. Get your grass healthy & it should choke out weeds & other grasses. I'm surprised that the CGM didn't work for you. In my opinion, the two best products for your lawn would be a layer of good compost or an application of a good aerated compost tea. There are several companies in this area that can apply the tea to your yard. Ck the info below for way too much info.

http://www.dirtdoctor.com/view_question.php?id=795

Dchall_San_Antonio · Joined: 18 Mar 2003 Posts: 2011 Location: San Antonio,TEXAS

If CGM didn't green up the grass, then I'm going to make a wild guess that you've had a lot of rain. That rain will leach out any acids your soil has developed. The resulting alkaline condition will bind up all your iron and it will not be available to the plants no matter how much protein or nitrogen you provide. What you need then is greensand. Nobody seems to know what the mechanism is by which greensand works, but it DOES work!! It is the only thing, short of waiting until next spring, that will green up an alkaline yard after heavy rain.

abraham1964 · Joined: 08 Aug 2006 Posts: 1 Location: dallas,TEXAS

btg wrote: KHWOZ: thanks for your advice, i haven't watered as much an it seems as if the yellow spots are slowly dissipating. I have a lot of a blue green type of grass that is growing in the yard and it wasn't there last year. How can i get rid it short of attempting to pull it up. I also used CGM on the lawn and it did nothing to green it up, in fact, the front has turned somewhat lime green in color. what is the best product or products to use for greening and this unknown grass in my lawn? what does the Garrett juice do and what about molasses? where do i get this tea product i hear people talking about? lots of questions, point me in the right direction. i appreciate it. btg

Texican · Joined: 13 Sep 2006 Posts: 14 Location: San Angelo,TEXAS

I know this topic is a little old and dated, but check this website to determine if your St Augustine has the fungal disease – Take-All-Root-Rot (TARR):

http://www.plantanswers.com/root_rot_fungus.htm

TARR is very common in Texas and a top-dressing with peat moss will greatly correct the problem.

lou_midlothian_tx · Joined: 01 Dec 2005 Posts: 113 Location: Midlothian,TEXAS

Texican wrote: I know this topic is a little old and dated, but check this website to determine if your St Augustine has the fungal disease – Take-All-Root-Rot (TARR):

http://www.plantanswers.com/root_rot_fungus.htm

TARR is very common in Texas and a top-dressing with peat moss will greatly correct the problem.

Howard won't even touch peat moss and corn meal works better.

Texican · Joined: 13 Sep 2006 Posts: 14 Location: San Angelo,TEXAS

Please tell me about this corn meal treatment. I've been reading a lot about it but have no experience with it all. Does it correct TARR problems?

lou_midlothian_tx · Joined: 01 Dec 2005 Posts: 113 Location: Midlothian,TEXAS

Corn meal feeds Trichoderma fungi which the population will mulitply and overwhelm bad fungi population by eating them! Preventative/cure is 20lbs per 1000 sqft every 3 months. Pretty cheap if you can find them. I get them from animal feed store, i think 7 dollars for 50lbs bag.

Of course, if you had used chemical fungicide in the past, corn meal is probably worthless unless you spread a thin layer of compost at the rate of 1 yard per 1000 sqft ti re-introduce fungi population to the soil.

Texican · Joined: 13 Sep 2006 Posts: 14 Location: San Angelo,TEXAS

Unfortunately, I did exactly what you said not to do and had the St Augustine sprayed with mancozeb (Fore) fungicide about 2 weeks ago. Well, after 30 years of doing this stuff, I’m still learning…

I’m going to try the corn meal treatment starting in about a month. Maybe by that time, the fungicide will have worn off.

Texican · Joined: 13 Sep 2006 Posts: 14 Location: San Angelo,TEXAS

Well, I did the horticultural cornmeal trick today. I spread 80 lbs of the stuff on 4,000 sq ft of St Augustine through a rotary spreader – what a messy job that was! I’m not sure if I got more of it on the grass or me.

I hit the TARR infested areas with a double dose of the cornmeal for good measure. Now I am waiting to see what happens.

When I was buying the cornmeal, I got a chance to talk to the nursery owner. I respect this guy’s opinion very much because he’s been doing this business for 40+ years. He’s a firm believer in cornmeal treatments for garden fungal problems. He also had a bunch of other products like lava sand, soybean meal, and half a dozen other products I can’t remember. Looks like I have some studying to do to find out about these products.

lou_midlothian_tx · Joined: 01 Dec 2005 Posts: 113 Location: Midlothian,TEXAS

HOpefully, there will be trichoderma fungi present in the soil to chew on corn meal. Remember, using chemical fungicide in the past can severely or wipe out fungi population in the soil. The only way to reintroduce them to the soil is spreading compost. It will take about 3 weeks for corn meal to start working. I know it's messy... I put them down yesterday while it was blowing. What a mess... I had to hand spread it...

Soybean meal is an excellent organic fertilizer if you needed extra nitrogen boost for faster growth/coverage. I plan on using them in feburary to speed up green up and thicken st aug lawn before weeds get a hold hopefully. Soybean meal is the easiest meal to spread with the rotary spreader. I get soybean meal and corn meal (unlicensed) at animal feed store for much less cost. around 7 dollars for 50lbs a bag.

That's pretty much it other than greensand that I put down twice a year. Pretty good source of iron for alkaline soil. 40lbs/1000 a year will probably do the trick for me. Pretty cheap at Lowe's. I use lava sand to mix with greensand to make them alot more spreadable. Greensand just sticks together. Nothing special about lava sand except for breaking up greensand...

Not sure about molasses... it might be useful on lawn, etc that are in poor condition . It basically boost microbial population quickly. I would think applying protein based grains and molasses together will improve condition more quickly. Look for UNSULFURED type. It might not work as well on lawn, etc that are good condition.