Fungal disease creating drought stress in zoysia?

8 years ago

We've had extremely high temps and very sporadic rain for the last three weeks or so (95+, sun). I've been battling large patch disease in my backyard zoysia for a while now (other thread). My questions are: is large patch active in the extreme heat of summer? Various posts and state ag recommendations are to begin watching out for this disease when summer cools off into fall.

I don't see any classic signs of fungal infection in my zoysia (leaf spots, yellow stems, rot in the stolons). However, the areas around the diseased patches look really wilty / dried out:

Compared to healthy lush a few feet away:

I have a lot of diseased spots (three large ones) and a lot of healthy spots, and each one occurs both in the sun and shade, near trees and free standing, so I'm thinking this is related to the disease.

As a side note, I planted fescue seeds in the patch last year just to have SOMETHING in the giant brown circle, but all the fescue in the ring itself died this May almost over night, so I'm thinking there's still a nasty agent circulating in there.

View of the diseased patches:

Sort by:Oldest

Comments (8)

dchall_san_antonio
8 years ago
That's what the disease looks like in the zoysia lawns in my neighborhood. Does yours go dormant (brown) in the winter? Overseeding with rye is fraught with peril. If that is typical diseased zoysia, it will not return to green until next April no matter what you do. In the mean time it would not hurt to put some corn meal down (20 pounds per 1,000 square feet).

Are you in the DFW area?
Spectrograph (NC 7b)
Original Author
8 years ago
Durham, North Carolina. I plan to nuke it with fungicide in August / September this year. I really want to halt the spread of the disease before I try gentler programs for this area. If I can get a clear halt, at least, to the disease, I'll pivot to cornmeal and compost immediately after to at least maintain.

By the way, do you have any experience de-thatching zoysia? That's just this year's thatch buildup you can see in the top close up. I've sprayed molasses twice. It takes time to work, but zoysia has really tough thatch I've heard.
Related Discussions
Empire Zoysia Grass
Q
Comments (17)
Our company is the developer and patent holder of Empire Zoysia. We do not recommend a 1-0-1 fertilizer, but rather a fertilizer with a 1-0-1 ratio. An ideal fertilizer would be a 15-0-15 in the spring, or a 20-0-15 if your lawn appears to be lacking in nutrients. One way to get the green without the N is to use iron that can be found in products such as Ironite. Be sure to apply an insecticide such as Bayer Advanced Grub control annually in the spring to prevent billbugs and other insects. Empire is typically pretty resistant to fungus and disease, but occasionally in wet conditions problems can arise. If you see sudden browning in spots, it usually a fungus issue and a systemic fungicide should be applied and will cure the issue. The link I included is to the maintenance page for Empire on our site. If you have any other questions let us know. If you would like more info on fertility, be sure to check out the post on understanding fertilizer on our Turf Talk blog. Good Luck! Drew Wagner Sod Solutions Inc. Here is a link that might be useful: Empire Zoysia Maintenance Schedule
...See More
Replace tall fescue with zoysia?
Q
Comments (5)
Texas Weed wrote: "Zoysia is a lower input grass than Bermuda or Fescue." In its native climate it might be, but certainly NOT in the transition zone. "Only needs mowed once every 7 to 10 days because it grows much slower." This is incorrect if you follow the 1/3 rule. It is recommended that Zoysia be cut at 1 1/2 inches and with a reel mower, which most if not nearly all homeowners do not have. At that height and with ideal summer conditions, Zoysia will easely grow 1 inch in 1 week or more. "Very drought tolerant and only needs 1/3 the water of Fescue requires to keep it alive and green during the hot summer." This is the biggest misconception out there. At the recommended mowing height of 1 1/2 inches, soil moisture will be depleted MUCH faster than a Fescue lawn cut at 4 inches high; the recommended height. "If you use a good cold tolerant variety like Meyers (Z-52) you should have a green lawn from April to October in your area." Get real! Meyers is a 50 year old variety that it's prone heavy THATCH and disease; and takes forever to recover from damage. Most Zoysia grasses here are always "under construction" despite good irrigation and fertilization schedules. The only good looking Zoysias here are at the Golf Course; where it can be pampered and maintained by professionals and virtually unlimited budgets. There's no real benefit to replace Tall Fescue with Zoysia, especially if you already have irrigation. If you don't like Fescue and have irrigation, then you could try Kentucky Bluegrass; which will stay green year round in your climate, create a dense turf, and spread via rhizomes just like Zoysia - not to mention it is actually dark green vs bright green Zoysia. Recommending Zoysia as a home lawn in the Transition zone is like recommending Bentgrass in the North. Some Zoysia varieties produce one of the nicest turfs of the warm season grasses if not the nicest in my opinion, but under the proper management and climate.
...See More
Yellowing Meyer Zoysia
Q
Comments (14)
Both of you raise some good points. Even when I water for a long time, I've never gotten to the point of runoff, so I think there's some decent penetration going on. We've gotten into a period of cool and damp weather, so I'm probably not going to put more water on the lawn now as in September last year was when the fungal problems started. If we get into a hot and dry spell yet this season I may experiment with what you say, maybe run two cycles back to back to see if I can go deeper and less frequently. Next year, I'll certainly try this method. With the fungal problems, I was trying to not leave the lawn wet too much overnight, so was trying to start the cycle about 3:30am and have it be done by the time we took showers (~5:30) due to the impact on water pressure in the house. So that was not a very long window to water, but maybe I will try bumping back the start time to 2am or something and run the two cycles. We have some odd habits here. I have the zoysia in the front and sides, and tall fescue in the back. Two completely different care requirements but typical around here. So when I mow, I have to adjust the cutting height betwen the front and back. The back yards tend to be shaded, so often the builders or homeowners plant fescue back there. Some of my neighbors put down bermuda sod, as expected it is not doing well as it only gets about 3 hours of sunlight. Also, the climate here does not really embrace any one type of grass. We are sort of in a turf grass no-man's land. The warm season grasses do OK but the growing season is only about 5 months. Cool season grasses like fescue look great in spring and fall but peter out in the heat of summer. There is really not one good all around choice so that's why there are so many varieties around here. I grew up in the north with KBG, and had St. Augustine in Texas, never saw such a duke's mixture like here. Also, this yard has been behind the eight ball from the start. Planted in mid 2006, 2007 was very hot and then drought, severe drought in 2008 and complete ban on outdoor watering so it suffered. This year has been pretty normal rainfall but Mother Nature has not been my friend since I've been struggling with this zoysia.
...See More
Zoysia in Central Florida
Q
Comments (3)
I've seen zoysia plugs sold in a garden center on the coast in st. lucie county when I lived there briefly. The thing with zoysia is that it establishes very slowly. There are some nice looking varieties in my opinion those are the darker, finer bladed types like emerald but those tend to be the ones that are the most disease prone. The only plugs I saw in florida for zoysia were the Empire type and that looks just like St. Augustine to me. Zoysia would very likely be what I was growing if I lived in florida. Either that or Bermuda or Seashore Paspalum. The latter two are a bit more maintenance intensive but can create a very nice high quality turf and definitely uncommon for central florida where nearly 99% of the homes either have st. augustine or bahia. Neither of those toot my horn.
...See More
dchall_san_antonio
8 years ago
I don't see any thatch. When you do water, how often and for how long?

With whatever fungicide you consider, read the entire label to see that it works at the daytime heat you're experiencing. Also make sure it's safe for zoysia.
Spectrograph (NC 7b)
Original Author
8 years ago
Would you not consider the layers of grass straw that's built up in the first picture thatch? If I take a metal rake to it I can get bushels of it.

I try to avoid watering my lawns at all cost (I love the warm season grasses).

I was going to wait until late August to use any fungicides.
dchall_san_antonio
8 years ago
That's just dead grass. Let the soil microbes work on it. For one it keeps the soil cooler in the summer and allows the microbes to work in cooler temps. Secondly it's their food. It's like mulch mowing to provide more nitrogen to the soil.

Thatch usually forms when you water and feed too frequently. I suppose there are other conditions it can form under, but with normal care it's not usually an issue.
Spectrograph (NC 7b)
Original Author
8 years ago
What would you consider the difference? I was worried because various sites say thatch can hold in excess moisture and promote fungus growth.
dchall_san_antonio
8 years ago
Thatch is a build-up of organic matter which can include, dead grass leaves, stems, stolons, rhizomes, and overcrowded grass roots and lateral weed growth (Wikipedia). I can live with that definition. Key is build-up. You have one layer of fallen over dead grass. I don't think that meets the definition. I guess when I rake up the leaves I'm dethatching. Have you tried raking up the dead grass?

The reason not to use a mechanical dethatcher is it is abusive to the turf. If you have stolons it will chop them into pieces. For St Augustine that can kill the plant. Zoysia is mostly spread with rhizomes, so you would not see it, but with a rake you can be a lot more selective as to how much of a beating the turf gets.
Spectrograph (NC 7b)
Original Author
8 years ago
Yeah I raked it last year. It was far more work than I was expecting so I was trying molasses this year.

Fungal disease creating drought stress in zoysia?

Comments (8)

dchall_san_antonio

Spectrograph (NC 7b)
Original Author

Related Discussions

dchall_san_antonio

Spectrograph (NC 7b)
Original Author

dchall_san_antonio

Spectrograph (NC 7b)
Original Author

dchall_san_antonio

Spectrograph (NC 7b)
Original Author

COMPANY

BUSINESS SERVICES

GET HELP

CONNECT WITH US

Fungal disease creating drought stress in zoysia?

Comments (8)

dchall_san_antonio

Spectrograph (NC 7b)Original Author

Related Discussions

dchall_san_antonio

Spectrograph (NC 7b)Original Author

dchall_san_antonio

Spectrograph (NC 7b)Original Author

dchall_san_antonio

Spectrograph (NC 7b)Original Author

COMPANY

BUSINESS SERVICES

GET HELP

CONNECT WITH US

Spectrograph (NC 7b)
Original Author

Spectrograph (NC 7b)
Original Author

Spectrograph (NC 7b)
Original Author

Spectrograph (NC 7b)
Original Author