Red Thread Disease - Laetisaria fuciformis
A disease of lawns in the late summer and autumn months, especially in lawns of low fertility, especially Nitrogen. If the summer months are humid and moist there will be an incredible outbreak of this disease on UK lawns.
Identification
This disease is now thought to be a combination or complex of two fungal species:
a) L.fuciformis – Red Thread – where the red needles are present
b) L.fuciformis – Pink Patch – where the pink mycelium is present
Red Thread is a very common turf and lawn disease. It occurs during mid to late summer and autumn and can persist into mild winters, especially if the weather is humid and damp. As with any other lawn disease, early and correct diagnosis is important. It is commonly seen as little red needles emerging from the leaf of the affected grasses or as a pink ‘cotton wool’ on the surface of the lawn. Affected areas can be the size of a golf ball but can coalesce into larger areas. Ill-defined patches of bleached grass. Pink mycelia are often seen visible in morning dew cover. Red needles are present attached to the leaf blades. Needles (stroma) become brittle on drying and serve to spread disease into new areas.
Where has it come from?
Red Thread naturally occurs as a Pathogen within the turf grass seed and ultimately the mature grasses. The grass seed breeders work hard to cultivate species and varieties of grasses that have ‘freedom of Red Thread’ pathogens. Buying certified and quality grass seed with known Species and Cultivars in the mixture is a good start! It can occur mostly in turf and lawn areas of low fertility levels, particularly Nitrogen. As grass growth slows down due to a lack of Nitrogen, the disease becomes more prevalent. If an area of lawn has recently been fertilised and some of the lawn was incorrectly missed and remains unfertilised, you will get more disease in the part that was not fertilised properly. Remedy this small strip or area by fertilising the missed areas.
Will it kill the lawn if left untreated?
Red Thread does not actually kill the grasses, merely making them look a bit straw like and unsightly, especially once the disease has caused the damage and dried up. Grass plants are rarely totally killed.
Grass species involved
Red Thread Disease can affect most turf grass species, but particularly Red Fescue (Festuca rubra) and Perennial rye grass (Lolium perenne) although the majority of cool season grasses as found in the United Kingdom can suffer an outbreak
What are my options on control of the disease?
Improve fertility levels immediately, especially Nitrogen and Potassium. Feeding a lawn little and infrequently is the worst culprit! Adopt a regular planned feeding programme. Summer control can almost always be assisted by the application of Nitrogen. Winter attacks also pose a problem on fine lawns and an adequate nutrient level must be maintained if the lawn has a history of attack.Choose disease resistant cultivars for initial sowings, repair and over sowing. Maintain a soil pH of 6.5-7.0. Ensure the lawn is mown with a mower with a sharp blade so that the grass leaf is not damaged and weakened. There is little benefit to be gained from an application of a turf fungicide.
Sometimes, even if you are fertilising your lawn on a regular basis, your lawn may still get an attack of Red Thread Disease but not as bad as an unfertilised lawn. The lawn will be telling you that nutrient levels are getting low in the soil's nutrient bank account! React to what the lawn is telling you!
A downloadable .PDF version Red Thread Disease is available here
Nice article. Red thread disease is a fungal infection found on lawns and other turfed areas. It is caused by the corticioid fungus Laetisaria fuciformis and it has two different stages. The stage that gives the infection its name is characterized by very thin, red needle like strands extending from the grass blade. Thanks.
Posted by: [email protected] | September 19, 2018 at 06:34
I have red thread fungis on my lawn. I have a landscaper who cuts my grass on a regular basis. He never mentioned to me about what was wrong with my lawn, I'm sure he had to know. What is the best course of action for me. Thanks Pat.
Reply - It is a shame that your Landscaper is not aware of a simple lawn fungal disease but hey, that is why our blog is so successful. Fertilise your lawn with some granular lawn fertiliser from www.thelawnshop.co.uk and repeat every three months.
Posted by: Pat Tobias | July 28, 2017 at 22:58
I have had a red thread problem for years. It is worse this year, since it has been a very rainy spring. I tried so many things, fungus control, lime, high nitrogen feed and it comes back every year after about 4 or fifth spring cutting. Tried malorganite, waiting to see.
Reply - Simply keep the nutrient levels up, Nitrogen and Potassium and it should be kept at bay unless there is a rapid change in the environment of warm, moist muggy weather.
Posted by: John | June 05, 2017 at 18:27
Hi with regards Red Thread i have a lawn specialist who treat my lawn every month. They have been treating Red Thread since June it is September and it is still there. My question is should this be the case, or when treated should it be away by this time. They dont take soil samples so how can they tell if it is lacking nitrogen, as having read here.
Cheers Les
Reply - Red Thread is a grass seed genetic problem. They need to apply more units of Nitrogen, so more fertiliser. Or apply a lawn fungicide like Bayer Lawn Disease Killer.
Posted by: Mr Les Millar | September 09, 2015 at 17:10
I have suffered from red thread on a newly seeded lawn in Hampshire UK. For the first time in 4 summers the lawn is disease free. I top dressed the lawn with "Pro Grow" from Veolia in the autumn and fed the the lawn from April to June with a nettle fertiliser (nitrogen rich) and a proprietary weed and feed. I firmly believe that top dressing is the most significant factor in controlling the red threat.
Reply - we use the trade equivalent of Pro Grow to top dress lawns and it is a great organic material! Totally agree with your comment and interested in the bit about Red Thread resistance.
Posted by: David | September 08, 2014 at 22:03
I have read all the articles on red thread, and yes, my grass burns out and dies after affected. (We live in Pittsburgh, PA) I have fertilized. Penn State and Rutgers have good postings on resistant varieties of perennial grass. But where do you buy it?
Thanks,
Pat
Reply - search online for a professional golf course grass seed supplier.
Posted by: Pat | September 13, 2013 at 17:47
What a great blog!!
Reply - Thank you
Posted by: | March 21, 2012 at 12:14
The federal government is encouraging farmers to spread a chalky waste from coal-fired power plants on their fields to loosen and fertilize soil even as it considers regulating coal wastes for the first time.
Reply - Interesting .....
Posted by: | December 09, 2011 at 06:15
My lawn was laid 2 years ago by a local supplier and was supposedly grown from Rolawn seed old lawn taken up topsoil laid and then turf, initially looked really green.
Since I had it laid Green Thumb have come quarterly to maintain.
We have now considerable Red Thread, any suggestions. Green Thumb say we need the lawn scarified and aerated, but will this get rid of the red thread
Reply - Go to www.grassclippings.co.uk and type Red Thread in the site search facility for a technical article on the subject.
Posted by: Jeanette Hooper | October 25, 2010 at 12:19
Jay
You can sometimes see a light pink fungal growth in the mornings on affected areas, sometimes called 'Pink Patch'. You can use a wide range of contact and systemic turf fungicides to control an outbreak but fertilising the lawn is the best remedy. Hope this helps!
Posted by: Mike Seaton | August 24, 2009 at 17:05
if i do have red thread, it is a pink and crystally looking on the patch itself.. in the early morning dew. if it is i am looking for a natural method to neutralize it. use a natural fertilizer. 15-8-7 or something like that. is there a natural way to dispose of fungus. can i use pl
ant fungicides.
Posted by: jay | August 17, 2009 at 15:45