First time post.

I live in Fenton MO (suburb of St Louis MO)
I have a Zoysia lawn.
I fertilize in mid-spring with Scotts with Halts. I generally do not fertilize again. To deal with what I believe to be a fungus attack, I have applied a fungicide for lawns but I don't have the container and don't remember the manufacturer.
I irrigate only in July and August, only as needed. Irrigation is not automatic.
It is an established lawn, I believe over 15 years.
I mow at a level of about 4".
I have not had a soil test.

My question is based on problems that I had 3 seasons ago and now is attacking another part of the lawn. Here is overall view of the lawn:

{{gwi:113034}}

This is a close photo of an unaffected section of that lawn:

{{gwi:113035}}

Here is a photo of the affected area:

{{gwi:113036}}

Here is a photo of a wider view of the affected area:

{{gwi:113037}}

Three seasons ago I had the same thing in another area. I applied a fungicide with a bit of water soluble fertilizer. I plugged the lawn with zoysia plugs the next season and they are filling in. I added more plugs again this season and they are doing fine. Here is a photo of the area:

{{gwi:113038}}

Not completely better, but better than it was. What you are seeing is zoysia and some weeds, primarily Oxalis and crab grass. Generally, zoysia will crowd out weeds and did for many years.

My question is, is this a fungus and is there anything I can do to stop the spread (seems that the fungicide and light fertilizer helped three seasons ago. I'd like to be more proactive, I guess. I don't want to apply chemicals needlessly, but I want to help the lawn.

I do not have a preference between synthetic or organic solutions. However, I would love to find something that works, if possible.

Thank you for any help!

Mike

bump once

You are mowing at 4 inches. WHY?

Looks great, I mow mine at 3" and it looks good. Somepeople are going to say 4" is too high but the grass will grow good short or tall.

as for the problem.
Hit it with either dylox or sevin. I would put money on it that you have a billbug problem.

texas-weed

I went out and measured the height and it is closer to 3" -- sorry for the mis-information. Is height an issue here? I mulch after the zoysia has a chance to come in and get rid of some of the winter dead leaves.

botanicalbill

I never even considered insect problems -- I guess I thought zoyzia was immune to everything! Obviously not!! I have some Sevin and I'll get it down in the areas tomorrow. Thank you for your help -- much appreciated!!

Mike

I'm in STL as well and have had similar problems with zoysia. It's hard to get knowledgeable advice from the garden centers about zoysia here. I was thinking that it was a fungus or disease. Did going after the bugs resolve your issue?

Thx for any insight!

Do you know what kind of zoysia you have? Since you live in St. Louis like me, I'm guessing it's Meyer Zoysia, also known as Z-52. Meyer is one of the most cold-tolerant varieties of zoysia and it "spreads much faster than other varieties," according to the quotation near the end.

Meyer does great here in the Transition Zone but not as well down in Florida. In Florida the El Toro variety of zoysia does better, according to NTEP results. Some other varieties of zoysia are also used in Florida.

The Meyer and El Toro varieties are in the species Zoysia japonica. Many Zoysia japonica varieties do well when cut to a height of 2 to 3 inches, but Meyer isn't one of them. Meyer should be cut to a height of between 1 and 2 inches. So far in March, I've cut mine to 2.6 inches in height, 2 inches, and 2.25 inches. I'm going to stick to 2 or 2.25 inches for the remainder of this year. I would cut it even lower--at least every once in a while--but my lawn isn't the most level.

Unlike the cool season grasses like bluegrass, fescue, and perennial rye, Meyer grows thick when it's cut short. When you cut it, I read somewhere that the cutting stimulates it to grow thicker, instead of more upward. Being so thick, it can crowd out weeds. The cool season grasses need to grow tall to shade out weeds. The cool season grasses aren't as thick as Zoysia. Zoysia is so thick, it's almost like a carpet.

If you have very tall zoysia right now, don't cut it down to 1 or 2 inches all at once. Remove just 1/3 of the blade. If it's still too high after the mowing, wait 3 or 4 days, then adjust your lawn mower's wheel height to remove another 1/3 of the blade. This is how you can get a 4- or 5-inch tall zoysia down to a better zoysia height of 1 to 2 inches.

If you cut off more than one-third of the blade, you hurt the grass's roots, whether it's a warm-season grass or cool-season grass.

I can't help you with the disease or bug issue your zoysia might have, because I've only been learning about and experimenting with lawn grasses for 10 months. The billbug idea someone mentioned sounds like a reasonable possibility to a novice like me, or maybe nematodes, but I really don't know. Hopefully, others here can help you with that.

If it were me, I'd lay off of the Halts and other synthetic chemical stuff. Just maybe too many synthetic chemicals are taking a toll on your zoysia, making it more disease / bug susceptible. I dunno, but organic is a safer way to go for both fertilizers and herbicides.

Regarding cutting height, here's a good quote from
http://askville.amazon.com/Zoysia-grass-grows-Central-Florida/AnswerViewer.do?requestId=8153335

"If fertilized as recommended, zoysiagrasses will require frequent mowing (e.g., weekly) during the summer to look their best. Zoysia japonica should be mowed every 7 to 10 days, or when it reaches a height of 3 to 4 inches. It should be mowed at a height of 2 to 3 inches with a rotary mower. 'Meyer' zoysiagrass looks best when cut at 1 to 2 inches every 10 to 14 days, or when it reaches a height of 2 to 2.5 inches, using a reel mower. 'Emerald' and Manilagrass should be cut with a reel mower at 1/2 to 1 inch every 10 to 14 days, or when they reach a height of 3/4 to 1.5 inches. Because zoysiagrass leaves are very coarse, they can be quite difficult to mow. A sharp, well-adjusted rotary or reel mower should be used."
[End of quote]

There's a lot of good info about zoysia on that web page. Here's some specific info about Meyer Zoysia: "Meyer zoysiagrass, also called Z-52 or 'Amazoy', is an improved selection of Zoysia japonica released in 1951. 'Meyer' is the zoysiagrass often advertised as the "miracle" grass in newspapers and magazines and has long been the standard zoysiagrass in use. It has a deep green color, medium leaf texture, and spreads much faster than other varieties, although it produces few rhizomes. 'Meyer' makes an excellent turf once established. It is less shade tolerant than 'Emerald', but is one of the most cold tolerant zoysiagrasses. Hunting billbugs and nematodes pose serious problems with 'Meyer', limiting its use in Florida."

>"I dunno, but organic is a safer way to go for both fertilizers and herbicides."

Can you cite some references of these "organic herbicides"?
I'm confused, those (you used plural) sound like an oxymoron.

To the OP - the area in question, why was it mowed in a different direction?

Garycinchicago wrote:
> Can you cite some references of these "organic herbicides"? I'm confused, those (you used plural) sound like an oxymoron.

Why yes, I can, Gary. Plain old scalding hot water boiled up in a kettle is an excellent organic herbicide. It kills just about everything fast. One has to be really careful about not killing the grass with this one.

Another superb organic herbicide is 5 percent distilled white vinegar, available at your grocery store. You can buy higher percentages of vinegar to water (maybe 20 percent) at some garden centers, but be extra careful about not hitting your grass with it. Even the 5 percent will harm the grass. Use a cardboard shield or something to protect the grass when you spray your vinegar from a spray bottle.

If someone wants to get fancier, Sandy Baker in her Complete Guide to Organic Lawn Care offers a recipe for a Citrus Vinegar solution:
[Quote] "To create this mixture, you will need 1 gallon of vinegar, 1/4 cup orange oil, 2 tablespoons dish detergent, and 1 cup lemon juice concentrate. Combine the dish detergent, vinegar, lemon juice, and orange oil in a large bowl. Stir the ingredients well and pour into a spray bottle."

Solarizing also works to kill unwanted weeds and grass. Look up solarizing, Gary.

There are at least a couple other organic methods you can use, too, that won't subject your grass to synthetic chemical assaults. If you want to use synthetic chemicals, Gary, go right ahead, but you asked me for organic methods. You might consider reading Paul Tukey's Organic Lawn Care Manual in addition to Sandy Baker's book.

Who are you guys talking too? The OP has been gone for 2 years.

I suppose those are all organic herbicides, but by that logic, so is a rock, or a blowtorch. The problem is that none of those methods are selective, and some are just unreasonable, like solarization. Sure I know what it is, and how it works, but to solarize an area of your lawn for some weeds mixed in will result in everything being dead, and it will take at least a month of having plastic sheeting on the area. Solarization is really used for lawn renovations, not removing the odd weeds in your yard. Also you say organic methods won't subject your grass to synthetic chemical assault, but it sounds like those organic methods are more damaging to your lawn than a properly used selective herbicide. If I spray chickweed that is intermixed with grass with a triclopyr, in a week or two I am left with grass, whereas with say concentrated acetic acid, I will have spots of dead grass. What do you do if you have a large area of healthy grass mixed in with an easily defeatable weed like chickeweed, or spotted lady thumb? Are you going to individually paint each weed with a small brush, or spend hours individually pulling out each weed?

Zoysia pests:
Dollar spot, brown patch, take-all patch, and leaf rust.
Spittle bugs, grubs, mole crickets (more so in the south), and billbugs.
Call the Missouri extension service in your area to get some help. When I looked at the MSU extension service site, I didn't think it to be very helpful - perhaps, in part, because you are in the northern zones for Zoysia. Some of the more southern states' extension services are much more informative - and all have web sites. With their info you may have to be choosey as to how you will apply their suggestions. For example, a Florida, Texas or Georgia service might suggest 4 applications of fertilizer per year but I doubt that 4 would be appropriate for your lawn.

ZoysiaSod:

You said herbicides, with a S. Didn't you see that when I quoted you?

Boiling water and vinegar are NOT herbicides in my world. Crazy to think that my pickles are made with herbicides, isn't it? And solarization (which I'm familiar with but thanks anyway) isn't a herbicide either, is it now?

Solarize a lawn to kill weeds? I seriously hope that is a joke. You do not solarize a yard to kill weeds, you do it to kill everything, even the soil. Solarize will sterilize the soil killing everything.

On the sod farm we did this quite often to prepare the field for a new planting of sod to guarantee purity of the grass type and to meet certification requirements.

Well, you commit herbicide whenever you kill a plant. So hot water is herbicidal.

Likewise, I guess you could say heavy users of Ortho products are herbicidal maniacs--just teasing.

I don't want a "Stepford Lawn." Dutch white clover is welcome in my backyard and side yard, although I do pull it from my front yard. But I never pull Japanese clover from my front yard. It's very welcome in my front yard's zoysia. Japanese clover has such a low growth habit and is so well manicured (self-manicured), it doesn't even look like a weed--it blends in with Zoysia so well. Plus it provides lotsa nitrogen as a nitrogen-fixing plant. It's an annual too, so it will go away on its own. (White clover is a perennial, by the way, for the newcomers to lawn care.)

But the most selective herbicide is your front 2 hands. Maybe being organic means to be versatile and to employ a multifaceted approach--not just use synthetic chemicals for everything. The so-called selective broadleaf herbicides will harm your grass in certain instances. For example, using 2,4-D while zoysia is coming out of dormancy will damage your Zoysia, according to the Scotts Lawns book, although they don't mention that on the Scotts/Ortho bottle. Using 2,4-D in hot weather can harm your grass too. And synthetics will harm the beneficial microbes in your soil, even if they spare your grass. But they must take a toll on your grass too, because the Weed-B-Gon concentrate bottle used for broadcasting (instead of spot-treating) says not to use it more than twice a year on your lawn, IIRC.

Now I'm not saying don't use 2,4-D or other drugs on your lawn. Just saying I won't use them anymore. Tukey has a chapter in his book called "Get your Lawn Off Drugs."

In addition to the web page at

http://askville.amazon.com/Zoysia-grass-grows-Central-Florida/AnswerViewer.do?requestId=8153335

that I linked to in an earlier post above in this thread, here's another great web page with a lot of helpful tips for zoysia lovers.

The earlier link above to amazon askville makes reference to the University of Florida site, and the following link is to a University of Missouri site:

http://extension.missouri.edu/publications/DisplayPub.aspx?P=G6706

Some especially useful tips from the MU page:

"Established zoysiagrass requires less fertilizer than many other species for healthy, attractive turf. A seasonal total of 2 pounds of nitrogen per 1,000 square feet is ample. Excessive or untimely fertilizer applications can lead to problems such as fewer roots, more thatch, diseases, and more topgrowth that requires increased mowing."

[Remember, this writer at MU is talking about zoysia in Missouri. Things may be a little different in Florida--dunno, but I think I remember reading somewhere that zoysia in warmer climates could need an extra fertilization or two. All I know is my zoysia has never been fertilized and it's done great. This year will be it's first fertilizing.]

====

"Established zoysiagrass should be fertilized from May through August. Early spring (March/April) fertilization benefits weeds and promotes premature topgrowth before roots begin to grow. Late fertilization (September) may interfere with the natural hardening process before winter."

[ZoysiaSod's note: This year because of the unusually mild winter (4th warmest on record in St. Louis) and because of the very warm spring weather, the timetables seem to have been pushed up by a month. My zoysia is already 100-percent green, except for the dead scragglies from winter, so I'll be fertilizing soon--I really don't need to, I think, because the zoysia is already a beautiful deep green, but gotta unload those 2 bags of fertilizer I bought this year because of the 2,4-D scare from last year.]

Another choice tidbit from the University of Missouri site about zoysia:

"Zoysiagrass is mowed at a shorter cutting height (1-2 inches) than Kentucky bluegrass or fescue. In the spring of the year, zoysiagrass lawns may be mowed at the lowest setting on your mower to remove dead leaf tissue. This increases the greenup rate and allows easier and more uniform mowing during the growing season. The mowing height should be raised in September by 1/2 to 1 inch in preparation for fall.

"When mowing, never remove more than one-third of the leaf blade at any one time. Clippings need not be collected if they do not remain as clumps on the lawn surface."

And:

"Zoysiagrass is a drought-tolerant lawn grass that requires less water than Kentucky bluegrass to remain green and actively growing during the summer months. Watering usually is not necessary except during prolonged dry periods."

[Remember, this writer at MU is talking about zoysia in Missouri. Things may be a little different in Florida--dunno.]

The quotations above come from an MU page titled "Establishment and Care of Zoysia Lawns" by Brad S. Fresenburg, Division of Plant Sciences.