Return to the Lawn Care Forum | Post a Follow-Up

 o
Eliminating zoysia without chemicals

Posted by ZoysiaSod USDA 6a/AHS-Arbor 6 (My Page) on
Fri, Nov 25, 11 at 4:26

Everyone knows zoysiagrass is a tough grass to get rid of. Why anyone would want to get rid of it, I don't know because zoysia is so gorgeous in the spring and summer.
But I found a page at URI that claims you can get rid of zoysia naturally, without chemicals. Here's the quoted passage:

"Many people plant zoysiagrass with the hope that it will solve all their lawn problems. After observing it for one or two winters, some people change their minds and hope to eliminate it. Their task is not easy.

"If you do not wish to use chemicals, or if complete or fast elimination is not required, you can use the following procedures.

1. Fertilize in September and October only.
2. Raise the height of cut to 3 inches or higher. After several years, this type of management encourages the cool-season turfgrasses to overtake the zoysiagrass.

"Faster elimination is possible. You would have to kill the entire zoysia lawn with a non-selective weed killer such as glyphosate, then renovate and reseed (CAUTION: glyphosate is not available for sale in Rhode Island--you will need to order it from an advertisement in a gardening magazine or newspaper)."
[End of passage]

The web link is:
http://www.uri.edu/ce/factsheets/sheets/zoysia.html

Why would those 2 steps above (fertilizing only in September and October and raising the cutting height to 3 inches) encourage cool-season grass to overtake zoysia?

I can kinda see that the Sept/Oct fertilizing would favor cool-season grasses since they're waking up from their summer slumber while zoysia is falling asleep, but why would a 3-inch or more cutting height hamper zoysia in favor of cool-season grasses?

I think I usually cut my zoysia kinda high (because I almost always cut it on Wheel Setting 4 of a 5-setting mower. Would this step alone hinder my zoysia in favor of the cool-season grasses? I never fertilize in September or October.


Follow-Up Postings:

 o
RE: Eliminating zoysia without chemicals

Because you would be forcing Zoysia to grow when it should be going dormant which weakens it, at the same time fertilizing the cool season grass when it is at peak growing conditions.


 o
RE: Eliminating zoysia without chemicals

Thank you very much, Texas-Weed. That makes a lot of sense. I guess zoysia prepares for the winter by going into dormancy. If the zoysia is prevented or delayed from going into dormancy because of a late September/October fertilization, the zoysia will take a bigger hit from the cold weather. I guess an analogy would be a boxer who tenses his stomach muscles in anticipation of a blow to the stomach. If he isn't allowed to tense his muscles before the blow, the blow will cause more damage.

But I'm really wondering about my second question, if you or someone else happens to know the answer.

The quoted passage above says zoysia can be gotten rid of (without chemicals) over a period of time by doing 2 things:

1. Fertilize in September and October only.
2. Raise the height of cut to 3 inches or higher. After several years, this type of management encourages the cool-season turfgrasses to overtake the zoysiagrass.
[end quote]

I will never fertilize in September/October, but I cut my zoysia kind of high--at about 3 inches (instead of 2). I wonder if this step *alone* can favor the cool-season grasses over zoysia and maybe usher out zoysia over several more years?


 o
RE: Eliminating zoysia without chemicals

Best way to kill Zoysia and Bermuda is to solarize it in the summer. Then in late summer or early fall is the perfect time to seed cool season grasses.


 o
RE: Eliminating zoysia without chemicals

Thanks, I might solarize some Bermuda this summer, but I definitely love the zoysia and want to keep it. I'm just wondering if you or someone knows if mowing the zoysia at 3 inches (instead of 2 inches) is too high, and over the years, if this 3-inch mowing would hinder the zoysia in favor of the cool-season grasses? I'll never fertilize in September/October, but the high 3-inch mowing concerns me.


 o
RE: Eliminating zoysia without chemicals b

I forgot to add that a book I have lists the recommended mowing height of zoysia at between 3/4 inch and 2 inches. But I'm always mowing at 3.


 o
RE: Eliminating zoysia without chemicals

3 inches is too high for Zoyzia. What variety do you have?

If you have mixed Zoysia/Bermuda lawn 1-1/2 inches is a good compromise and both should do well. The real challenge is fertilizing the two. Burmuda is a nitrogen hog requiring 5 to 8 applications per season, and Zoyzia no more than 2 per season, or 3 in gulf coast regions.


 o
RE: Eliminating zoysia without chemicals

I think I have Meyer Zoysia, aka Z-52, aka Amazoy.

Only one percent of my lawn is Bermuda, and even less today, because I pulled more bermuda out this morning. What little I have is probably the Common cultivar of Bermuda. I understand they don't recommend the nicer-looking hybrid varieties of Bermuda for home lawns because the Bermuda hybrids are much more susceptible to disease and pests.

From what I read, a golf course superintendent probably could care well enough for hybrid varieties of Bermuda, but your average lawn owner cannot.

Back to Zoysia: I have read that if you mow your Zoysia too high, it promotes thatch, but I'm hoping 3 inches isn't thatch-promoting, or harmful to zoysia in any other way--even though 2 inches is the standard recommendation for mowing height.

I know I let some 5 x 5 inch square Zoysia plugs I planted grow to about 10 inches high without seeing any thatch at all inside the plugs. And I didn't notice anything else that was negative. I've since cut the plugs to a much lower height in preparation for winter.


 o
RE: Eliminating zoysia without chemicals

Bermuda hybrids are much more susceptible to disease and pests.

From what I read, a golf course superintendent probably could care well enough for hybrid varieties of Bermuda, but your average lawn owner cannot.

I am not sure where you heard that, but it is completely false. The hybrids have as good and most are more resistant to disease and pest. It is one of the characteristics they were engineered for.

I also think you would have around 100 million people disagree with you that an average homeowner cannot have a nice Bermuda lawn. I personally know around 10,000 of them that I either installed or sold it too them or both.


 o
RE: Eliminating zoysia without chemicals

I never said the average homeowner cannot have a nice Bermuda lawn [smile]. Please don't attribute things to me that I never said [another big smile].

I said that I read online that *Hybrid* varieties of Bermuda aren't suited for the average homeowner. I am just a novice, but that's what I read on a web site somewhere.

Just to clarify for myself and other novices reading this, there are *Hybrid* varieites of bermuda which are different from the *Common* varieties of bermuda.

Some *Common* varieties of bermuda are called "Cheyenne," "Yuma," and "Sonesta." These are all *Common* varieties of bermuda (or improved varieties of *Common* bermuda grass).

Then there are *Hybrid* varieties of bermuda like "Midiron," "Tiflawn," and "Tifway." The Hybrid varieties are totally different than the Common varieties. The hybrid varieties are crosses between Common bermuda (Cynodon spp.) and African bermuda (C. transvaalensis).

The above info about the differences between Common varieties of Bermuda and Hybrid varieties of Bermuda comes from the 2nd edition of the Scotts "Lawns" book (pages 190-191).

Here's a quote from the book:
"Common bermudagrass has relatively good drought tolerance compared with the hybrids, which tend to thin during extended drought periods."[End quote]

There are other differnces, including that the hybrids cannot be seeded. The hybrids are finer-textured than the common varieties, and I think, tend to look nicer.

Here's a quote from David Mellor's book "The Lawn Bible":
"Hybrids may need more care than common types and must be started by sprigs or plugs.
Maintenance Level: Average (common Bermuda grass) to high (certain hybrid types)." [End quote]

Interestingly, Mellor lists "NuMex Sahara" as a hybrid variety, whereas the Scotts book lists it as a common variety.


 o
RE: Eliminating zoysia without chemicals b

By the way, I forgot to ask you. What do you mostly sell to the average homeowner who wants a lawn: one of the Common varieties of bermuda or one of the hybrid varieties of bermuda? Thanks.


 o
RE: Eliminating zoysia without chemicals

Interestingly, Mellor lists "NuMex Sahara" as a hybrid variety, whereas the Scotts book lists it as a common variety.

That ought to tell you something. Nu-Mex aka Sahara is a common seeded variety released by NMSU in 1980 and funded by the USGA.

What do you mostly sell to the average homeowner who wants a lawn: one of the Common varieties of bermuda or one of the hybrid varieties of bermuda?

I do not know of any sod farmers that raise and sell Common Seeded Bermuda sod varities. All I know of sale only hybrids. Personally my farm sales only Tifway-II (improved 419 or Tifway-I), TifSport, and a small quantity if Tif Eagle which is a golf putting green variety. Now with that said my Son owns his own landscape company that uses my sod and investment capital and he does plant some common varieties via seed like Yukon-Riviera blend.

FWIW Tifway-I, Tifway-II, and TifSport dominate the market accounting for about 90% of all Bermuda sod sales. All the other added up do not even place a close second.

If you look at NTEP test results you will note that just about all the hybrids out perform all the common types in every category. When it comes to Tifway-I, Tifway-II, and TifSport, non of the common types come close. That is why they dominate the market in Bermuda grass sod sales.


 o
RE: Eliminating zoysia without chemicals

Thank you very much, Texas-Weed. That was really interesting info about Tifway II and TifSport.

It took a lot of searching, but I was finally able to find the web site again where I read that stuff I said earlier.

It's a U. of Florida site at this page:

http://edis.ifas.ufl.edu/lh007

Here are two quotations from the page:

"Because of the high maintenance requirements of the improved bermudagrasses, however, they are not generally recommended for use as a home lawngrass."

And

"Improved bermudagrasses require high levels of maintenance. They have poor tolerance to many insect, disease, and nematode pests, which limits their use in home lawn sites."

So it seems to me that maybe the University of Florida site is creating 3 broad categories of Bermuda, not two. If I'm understanding it right, the 2 professors who wrote that page seem to classify Bermuda into these 3 categories:

1, Common Bermuda grass (Cynodon dactylon)

2. Improved varieties of Common

3. Hybrid Bermuda grasses


 o
RE: Eliminating zoysia without chemicals

Well you need to take what FU is saying with a grain of salt and within context offered. For example this statement:

Improved, fine-textured bermudagrasses are used throughout the south on golf courses, athletic fields, and in high-profile residential and commercial landscapes where a fine-textured, dense ground cover is desired. Because of the high maintenance requirements of the improved bermudagrasses, however, they are not generally recommended for use as a home lawngrass.

To me this is double talk because improved fine-textured includes both hybrids and common improved types. Secondly it has me asking WTF, and I am certain thousands of the members on this forum would say the same thing because most have one of the really fine textured Bermuda grasses. Tifway-I is the most widely sold and available verities out there. It is the default choices for builders and contractors of the residential and commercial markets.

As for the finer textured varieties needing higher level of inputs is half true. They require to be kept short which means more frequent mowing, watering, and feeding. Si in that regard that are not a good choice for lazy people or those who do not value a beautiful yard.

As for the insect and disease resistance of the improved varieties I have no idea what they are talking about. All varieties of Bermuda grasses have fewer problems than any of the other warm season and all the cool season grasses. Bermuda grass is certainly not immune to pest and diseases but it is one tough cookie no other grass can compare too. It is so tough and aggressive it gets a bad name in some locations as it is almost impossible to kill.

As for comparing Zoysia vs Bermuda with respect to problems, Zoysia is plagued with a long list of insect and disease problems.


 o
RE: Eliminating zoysia without chemicals

It's kind of funny, but I'm beginning to think the word "improved" is more of a marketing term than a scientific term, even though the scientists at the U. of Florida use the words "improved varieties" too.

Improved in what way? Maybe the only way is appearance (density, deep color, finer texture).

The "improved" varieties of Common bermuda and the hybrid bermudas might look better than Arizona Common bermuda, but I'm beginning to think they're not better in robustness, health, disease resistance, and level of low maintenance.

For example, I'm guessing highway departments almost always plant Common Bermuda on the side of highways, not the so-called "improved" varieties or the hybrids.

But even universities seem to disagree about which bermuda is more disease-resistant. A page at the U. of Georgia (maybe a friendly rival of the U. of Florida?) states that the hybrids are "generally" more disease-resistant than the seeded types, which contradicts the U. of Florida's page. I wonder if "generally" excludes Common.

Also the U. of Georgia might earn royalties or some kind of compensation when certified hybrids are sold because there seems to be something called the "Georgia Crop Improvement Association (GCIA)."

There's a page at the U. of Georgia's web site that states in italics no less [quote]: "All of the improved bermudas described here have been developed and released cooperatively by the University of Georgia and the U.S. Department of Agriculture."

Here's the page:
http://commodities.caes.uga.edu/turfgrass/georgiaturf/Articles/BermudaManagement.htm

The page also says:
[Quote] "For the highest quality bermudagrass turf use sod certified by the Georgia Crop Improvement Association (GCIA). This grass is certified for its genetic purity and is free of noxious weeds like other bermudagrasses and nutsedge. This grass should be delivered with a GCIA blue tag verifying its quality." [End quote]

There is one seeded variety that's as good-looking as the hybrids.
From U. of GA: " "Princess" is the exception of the seeded types. This seeded bermudagrass has turf color, density and leaf texture, that produces turf quality very similar to "Tifway" bermudagrass." [End quote]. Tifway is a hybrid.

That's a very interesting page at the U. of Georgia--lotsa good info about the hybrids.

A commercial site (bermudagrass.com) provides an example where seeded varieties are more disease-resistant than the hybrids:

"DISEASE / INSECTS: Pearl Scale is a big problem on Tifgreen and other sodded Bermuda grasses. Unfortunately, there is no good method to control them on some of the improved vegetatively established Bermudas. The pearl scale feeds on the roots, so getting insecticide down in the soil where the insects are is difficult, and insecticides are not that effective against them. The best option in turf infested with pearl scale is to plant seeded Bermudagrasses which are naturally resistant to them. No one knows the mechanism of resistance in the seeded Bermuda grasses to pearl scale - they just never get infested with it."


 o
RE: Eliminating zoysia without chemicals

When it comes to Bermuda grass R&D there are two heavy hitters: Georgia University, and Oklahoma State University. FSU really does not have much to speak of except FloraTam Saint Augustine grass which was mostly developed by Texas A&M

You are right the universities have a vested interest in their product releases. U of G receives a royalty for every blade of Tif-(insert anyone of the dozens variety names they own here) sold.

FWIW though I would trust what U of G or OSU says long before FSU as they have a lot of third party testing to back it up.


 o
RE: Eliminating zoysia without chemicals

Wow, I found a ton of info at MU on the many varieties of Bermuda that are used for pastures. Varieties of Bermuda called:

Midland
Hardie
Guymon
Wrangler
Greenfield
Tifton 44
Midland 99
Quickstand
World Feeder

Here's the page for anyone interested:

http://extension.missouri.edu/publications/DisplayPub.aspx?P=g4620

Also, making a note about the Princess variety for lawns from BermudaGrass.com ( http://www.bermudagrass.com/info/princess.html ) :

"Princess 77...is the first and only true hybrid Bermuda grass available from seeds."

So there is one Bermuda hybrid that can be seeded, which surprised me.

I believe Zenith is a zoysia hybrid that can be seeded. Another zoysia variety that can be seeded is Compadre (formerly known as Companion before a trademark issue arose).

Found a couple sites that said zoysia can be grown to 3 inches instead of just the 2 that the Scotts Lawns book listed.

From http://www.zoysias.com/info/seeding-companion.html :

When & How To Mow Zoysia Grown From Seed:

"Start mowing the new zoysia seedlings as soon as they reach 2 inches in height and mow frequently to stimulate spread and reduce weed competition during establishment. A turf height of 1-2 inches in full sun and 2-3 inches in shade will produce the best results."

Another site (I've forgotten where) just says mow your zoysia between 1 to 3 inches.


 o
RE: Eliminating zoysia without chemicals

Wow, I found a ton of info at MU on the many varieties of Bermuda that are used for pastures. Varieties of Bermuda called:

Midland
Hardie
Guymon
Wrangler
Greenfield
Tifton 44
Midland 99
Quickstand
World Feeder

Well these types are classified as LOW INPUT, Low Quality common Bermuda grass types. It means they are designed to make either hay for livestock feed, erosion control, and highway ground cover. They are suitable for home lawns.

There are 3 grades of common Bermuda grass.

1. Low input or pasture grade.

2. Medium Input or basic no thrills turf grass for homes and commercial.

3. High input or semi-fine texture and good color. Suitable for residential/commercial turf grass, sports fields, and golf fairways/rough/tee boxes.

Princess 77...is the first and only true hybrid Bermuda grass available from seeds."

So there is one Bermuda hybrid that can be seeded, which surprised me.

P-77 IS NOT a hybrid. It is a improved common type in the high input category.

Found a couple sites that said zoysia can be grown to 3 inches instead of just the 2 that the Scotts Lawns book listed.

That is a bogus meaningless answer. Like any grass optimal mowing height depends on the variety. The coarse types can and should be cut high. On the other side is the fine dense textured vanities like Diamond that need maintained at 1 inch or less. Diamond Zoysia can be used for golf putting greens whitch require cut down to as low as 3/16 an inch.


 o
RE: Eliminating zoysia without chemicals

Texas-Weed wrote:
> P-77 IS NOT a hybrid. It is a improved common type in the high input category.

Thanks for your insights. They're always appreciated.

Regarding whether Princess 77 is a hybrid or common variety, the Pennington Seed Company also says Princess 77 is a hybrid.

Here's a quote from Pennington Seed at
http://www.penningtonseed.com/ProductDetails.aspx?id=104

"Princess 77 bermudagrass is the first dense, fine-textured hybrid bermudagrass variety to be available in seeded form. Princess 77 seed is produced much like hybrid seed corn, but instead of two inbred parent lines, two self-incompatible but cross-fertile parent clones are planted in alternating rows.

"The specific combining ability of these two elite parent clones is what makes Princess 77, an F1 hybrid, the first seeded bermudagrass that is competitive with the vegetative hybrid bermudagrasses for turfgrass quality, leaf texture, color, and density.

Characteristics:

* Outstanding drought tolerance
* Requires 21% less water than Tifway
* Dark green color
* Better divot recovery than Tifway
* Medium fine leaf texture
* High leaf density
* Excellent fall color retention
* Higher overall turf quality than all commercial seeded varieties in U.S. and International tests"
[End of Quote]

Also, I think some of the varieties on the MU site are also hybrids. The MU page states that:

"Midland is a F1 hybrid between Coastal and a winter-hardy common."

"Hardie is a sterile F1 hybrid."

"Tifton 44 was selected from several thousand F1 hybrids between Coastal and a winter-hardy common bermudagrass from Berlin, Germany."

But, yes, the others on that MU page appear to be common varieties, not hybrids.


 o
RE: Eliminating zoysia without chemicals

Zoysiasod,
Just follow the money trail to see why they say what they do. And the word all these sites like to use the most and that is "appears to be like?". That ought to raise a red flag.


 o
RE: Eliminating zoysia without chemicals

Neilaz wrote:
> Just follow the money trail to see why they say what they do. And the word all these sites like to use the most and that is "appears to be like?". That ought to raise a red flag.

Well, I thought scientists were suppose to act dispassionately and rely objectively on the evidence. But I think we see that even scientists disagree when presented with the same evidence, some interpreting the evidence one way while others interpreting it another way, I guess.


 o
RE: Eliminating zoysia without chemicals

Well, I thought scientists were suppose to act dispassionately and rely objectively on the evidence.

Yes they say that and hope everyone believes that but keep in mind where the money to pay for their research and salaries come from. About 90% of it comes from government grants, and/or government organizations.

The really high paying scientific jobs are in the private sector working for companies like military defense contractors, chemical companies, pharmaceutical manufactures etc.. Those who do not measure up end up working in the public sector like universities, government agencies like NASA & NOAA, and government grants. So it does not matter if they work in private or public sectors, they have a bias and loyalty to who pays for their research and salaries.


 o
RE: Eliminating zoysia without chemicals

I don't understand the need to do so much work to get rid of a plant. Grass is like any other growing plant, it has roots and uses water and soil to grow and needs sunshine to prosper. So, eliminating any of them should kill the plant.
The work involved to remove it may be an arduous task on a summer day but cover it with a black covering--any dark material that can be laid down, kept from blowing off, will kill the grass in short order.
Another thing, if you have some spare framed windows, laying them over a lawn will kill the grass in one sunny day.....even on an overcast day.
Then the problem of removing the resulting dead material is still necessary.
The best part of these types treatments, the soil is not affected, no chemical poison and the replacement seeding/sodding can be made as soon as practical.


 o
RE: Eliminating zoysia without chemicals

Texas-Weed wrote:
The really high paying scientific jobs are in the private sector working for companies like military defense contractors, chemical companies, pharmaceutical manufactures etc.. Those who do not measure up end up working in the public sector like universities, government agencies like NASA & NOAA...

Well, would you say Einstein who worked at Princeton, or Carl Sagan who worked at Cornell, or Robert Ballard (finder of the Titanic) who works at NOAA, are second rate scientists? These public sector geniuses are as good or better than their private sector counterparts :-)


 o
RE: Eliminating zoysia without chemicals

Well, now I feel better about cutting my Zoysia to a height of 3 inches. Paul Tukey in his book "The Organic Lawn Care Manual" (really an excellent book) writes that

Zoysia's mowing height is 2 - 3 inches.

This differs slightly from what the Scotts "Lawns" book says, which is that their recommended mowing height for zoysia is 3/4 - 2 inches.


 o
RE: Eliminating zoysia without chemicals

Some of Einstein's theory's are now being seen as being incorrect. Maybe He wasn't so smart after all.


 o
RE: Eliminating zoysia without chemicals

Zoysia's mowing height is 2 - 3 inches.
That is very bad advice the author is giving as there are many Zoysia varieties that perform best cut at 1 inch or less, like Diamond and Emerald used in golf course fairways and putting greens.


 o
RE: Eliminating zoysia without chemicals

Texas-Weed wrote:
That is very bad advice the author is giving as there are many Zoysia varieties that perform best cut at 1 inch or less, like Diamond and Emerald used in golf course fairways and putting greens.

Hmm, maybe Tukey is talking specifically about the seeded Compadre variety of Zoysia for the 2 - 3 inch mowing recommendation. I'm not sure though. It's a little hard to say because things are left a little unclear with the chart in the book.


 o
RE: Eliminating zoysia without chemicals

It's a little hard to say because things are left a little unclear with the chart in the book.

Sounds to me like you need a different book from someone who knows what they are talking about... From someone who actually does things and works with the subject in real world application. This guy sounds like the current POTUS, all academic with no experience or real world application.


 o
RE: Eliminating zoysia without chemicals

Texas-Weed, for sure, you are very right (real world experience is a must). Please let me say in Tukey's defense, he cared for hundreds or probably thousands of lawns for years and years before writing his book. He used to be a synthetic herbicide guy until switching to Organics.

Speaking about the mowing height of zoysia, it sure would be nice if companies made self-propelled walk-behind lawn mowers for which you could *exactly* control the blade's mowing height. My Troy-Bilt / Briggs and Stratton mower has 5 wheel settings. Setting 4 cuts at 3.25 inches and Setting 3 cuts at 2.625 inches. There's nothing in between, so I usually just cut at Setting 4.


 o Post a Follow-Up

Please Note: Only registered members are able to post messages to this forum.

    If you are a member, please log in.

    If you aren't yet a member, join now!


Return to the Lawn Care Forum

Information about Posting

  • You must be logged in to post a message. Once you are logged in, a posting window will appear at the bottom of the messages. If you are not a member, please register for an account.
  • Please review our Rules of Play before posting.
  • Posting is a two-step process. Once you have composed your message, you will be taken to the preview page. You will then have a chance to review your post, make changes and upload photos.
  • After posting your message, you may need to refresh the forum page in order to see it.
  • Before posting copyrighted material, please read about Copyright and Fair Use.
  • We have a strict no-advertising policy!
  • If you would like to practice posting or uploading photos, please visit our Test forum.
  • If you need assistance, please Contact Us and we will be happy to help.


Learn more about in-text links on this page here