Thatch and Fusarium Patch ...All About Balance

The M. nivale fungus resident in agement practices when environ- Fusarium and thatch 7 Soil profile thatch and stirred by cooler and mental indicators flag up periods from a golf green showing evidence wetter conditions is presented of high pathogen activity and high of thatch accumulation on the right (Picture courtesy Syngenta) with a new flush of foliar growth. sward susceptibility to Fusarium The pathogen moves up through patch disease. Verti-cutting and top the gears into full parasitic mode dressing offer less invasive thatch with Fusarium patch disease as management options. Applying a the invariable result. Most fungi systemic fungicide prior to hollow are great lovers of surface moisture core tining or deep scarification is and high humidity and M. nivale advisable. is no exception. High thatch levels The type of fungicide used and hold more moisture and generate when to apply continues to be more humid microclimates within the most hotly debated topic in the turf profile. Fusarium patch control for sports Feed turf by all means - but with turf. fertiliser formulations rich in potas- Mowing is the reason why turf sium to make the most of the ‘gate- exists but it is easy to forget the keeper’ nutrient with its intrinsic impact of continual low cutting on abilities in good water relations and turf and its susceptibility to disease. strengthening of grass plant tis- Mowing will clearly stress out sues. The acid reaction generated turf but also leaves behind grass by ferrous sulphate (iron sulphate) leaves with open cut ends as prime on the turf surface boosts resilience points for entry of fungal pathogens to Fusarium patch while deterring including M. nivale. Another disease surface casting earthworms. implication of mowing is removal of Hollow core tining and deep fungicide in the clippings, whether scarification are well worn methods contact protectant fungicide on the for reducing thatch and conditions surface of the severed leaf ends or which exacerbate Fusarium patch. systemic curative fungicide inside However, collateral physical the leaf tissue. damage increases turf stress as On the plus side systemic fungi- well as providing entry points and cide inside the leaf tissue will exude infection sites for the pathogen. in sap from the cut to provide a Advice given is generally against chemical barrier against infection carrying out these invasive man- by M. nivale. Evidence suggests Thatch and Fusarium Patch ...all about balance

Fusarium patch caused by the cannot remove the fungal patho- Presence of the pathogen and fungus Microdochium nivale is gen. M. nivale is always present about the author solution to the disease lie in the the most navel-gazed disease in turf usually as a saprophytic thatch and how it is managed. in golf course management, or weakly parasitic microbe living The intrinsic value of thatch set hardly surprising since M. in the thatch, the dead and dying against harbourage of pathogens nivale is the most important organic matter at the base of the and promotion of disease is all pathogen of temperate turf turf grass sward. about balance. You can’t exclude and Fusarium patch the Thatch is central to sports thatch and why would you want number one disease in UK turf and Fusarium is inherent to to? Naturally occurring thatch at sports turf. thatch. an appropriate depth and unifor- Fusarium patch attracts more Everything else including the mity provides a natural resilience cultural practices and fungicide aggravating effects of environmen- Dr Terry Mabbett which contributes to the speed and applications than all other turf tal conditions, inappropriately Dr Terry Mabbett is a disease, consistency of play. It also acts as diseases put together with the timed management practices and pest and weed control specialist with forty years a singularly significant ‘recycling prime aims of avoiding the disease the success or failure of fungicide international experience bin’ for natural nutrients (including covering research, advisory or removing its presence from golf application all comes back to a and journalism. His current nitrogen), released from decompos- greens. fungus with pathogenic potential fields of focus are professional ing organic matter and returned to turf and alien insect pests and Greenkeepers can avoid and residing in the thatch component pathogens of Britain’s native the living grass plant tissue through eradicate Fusarium patch but they of turf. and naturalised trees. the fibrous root system.

38 GI MARCH 2014 @BIGGALtd @BIGGALtd MARCH 2014 GI 39 THATCH & FUSARIUM

escaping fungicide is washed down the sides of the leaves and re-enters the plant. Chemical control of Fusarium patch is not a ‘one fungicide fits all’ scenario. It is clearly not advisable to rely on a contact protectant fungicide when grass is growing quickly because there will always be a high proportion on new unprotected leaf surface and because short interval mowing will be in place. By the same token there is not much point in using a systemic curative fungicide when the grass is not actively growing because uptake of fungicide whether by the root system or through the leaves will be limited. All things being equal a systemic fungicide taken up by either the leaves or the roots will provide a more effective option in relation to fungicide interception and absorp- tion by the grass plant. Recognition of thatch as central to the occurrence, development and severity of Fusarium patch is behind the latest development in turf fungicide technology and strategy. Fludioxinal the active ingredient in Syngenta’s Medallion targets and destroys M. nivale in organic matter (thatch) before it has chance likely be the only turf disease on the to become Fusarium patch disease ABOVE: Widespread Fusarium tible - and terminally so - to basal product label. patch beginning to dry out but on the living green leaves. rot anthracnose. Some greenkeep- Control of anthracnose was the damage has already been Fludioxinal appears to alter the done (Picture Courtesy Bayer ers have traditionally turned a essentially incidental and collateral Environmental Sciences) integrity and status of the selec- blind eye to anthracnose, reasoning to the primary effect of a broad tively permeable membrane which ABOVE RIGHT: Fusarium and that it will kill and clear out annual www.advancedtt.com bounds the spore. This results spectrum acting fungicide on thatch 6 Grass leaves with Fusarium patch disease simply add meadowgrass in what must have Fusarium patch disease. in rapid movement of water (by to the thatch burden on golf greens been one of the earliest examples Poa annua (annual meadow) (Picture courtesy Syngenta) EVEN MORE osmosis) into the spore causing it to of man-managed biocontrol in turf. grass continues to be the ‘black rupture and burst. Most modern fungicides are sheep’ of sports turf grasses with its Osmosis is the movement of small equally effective against Fusarium intrinsic susceptibility to Fusarium molecules such as water across a patch and anthracnose so appli- ADVANCED patch and high thatch forming selectively permeable membrane cations targeted at Fusarium credentials. Greenkeepers worried The incredible 22” INFiNiSystem™ now from a higher concentration [of will invariably control basal rot about high percentages of Poa has a big brother – a 26” wide version with water molecules] to a lower concen- anthracnose at the same time, annua in their greens, and result- all the same attributes. tration [of water molecules]. and therefore help to maintain the ing implications for Fusarium, are This wider model will increase productivity, Fusarium patch has always been high thatch producing Poa annua advised to reduce annual meadow- whilst the ﬂoating head will ensure no the number one target for new turf component in a turf grass sward. grass in favour of bent and fescue. compromise on undulating surfaces. fungicides. It is not that long ago It’s all about balance. when Fusarium patch would most Poa annua is even more suscep- SMART cassettes for ultimate turf 9 management

Power sources Dig deep! for maximum 2 flexibility The Redexim Verti-Drain™ is the choice of championship golf courses and top flight sports clubs to keep their playing surfaces Machine widths, in tip top condition. 22” and 26” for 2 more productivity 17 models make it the most comprehensive range of aeration equipment available - one to suit all applications such as high speed; deep tine; compact or contractor. TM Find out more about our Verti-Drain™ range today.

Designed for durability

www.charterhouse-tm.co.uk | 01428 661222 aerate brush de-thatch groom level mow scarify top dress

40 GI MARCH 2014 @BIGGALtd @BIGGALtd MARCH 2014 GI 41 THATCH & FUSARIUM

escaping fungicide is washed down the sides of the leaves and re-enters the plant. Chemical control of Fusarium patch is not a ‘one fungicide fits all’ scenario. It is clearly not advisable to rely on a contact protectant fungicide when grass is growing quickly because there will always be a high proportion on new unprotected leaf surface and because short interval mowing will be in place. By the same token there is not much point in using a systemic curative fungicide when the grass is not actively growing because uptake of fungicide whether by the root system or through the leaves will be limited. All things being equal a systemic fungicide taken up by either the leaves or the roots will provide a more effective option in relation to fungicide interception and absorp- tion by the grass plant. Recognition of thatch as central to the occurrence, development and severity of Fusarium patch is behind the latest development in turf fungicide technology and strategy. Fludioxinal the active ingredient in Syngenta’s Medallion targets and destroys M. nivale in organic matter (thatch) before it has chance likely be the only turf disease on the to become Fusarium patch disease ABOVE: Widespread Fusarium tible - and terminally so - to basal on the living green leaves. product label. patch beginning to dry out but rot anthracnose. Some greenkeep- Control of anthracnose was the damage has already been Fludioxinal appears to alter the done (Picture Courtesy Bayer ers have traditionally turned a Environmental Sciences) integrity and status of the selec- essentially incidental and collateral blind eye to anthracnose, reasoning tively permeable membrane which to the primary effect of a broad ABOVE RIGHT: Fusarium and that it will kill and clear out annual www.advancedtt.com bounds the spore. This results spectrum acting fungicide on thatch 6 Grass leaves with Fusarium patch disease simply add meadowgrass in what must have in rapid movement of water (by Fusarium patch disease. to the thatch burden on golf greens been one of the earliest examples (Picture courtesy Syngenta) EVEN MORE osmosis) into the spore causing it to Poa annua (annual meadow) of man-managed biocontrol in turf. rupture and burst. grass continues to be the ‘black Most modern fungicides are Osmosis is the movement of small sheep’ of sports turf grasses with its equally effective against Fusarium molecules such as water across a intrinsic susceptibility to Fusarium patch and anthracnose so appli- ADVANCED selectively permeable membrane patch and high thatch forming cations targeted at Fusarium The incredible 22” INFiNiSystem™ now from a higher concentration [of credentials. Greenkeepers worried will invariably control basal rot water molecules] to a lower concen- about high percentages of Poa has a big brother – a 26” wide version with anthracnose at the same time, all the same attributes. tration [of water molecules]. annua in their greens, and result- and therefore help to maintain the This wider model will increase productivity, Fusarium patch has always been ing implications for Fusarium, are high thatch producing Poa annua whilst the ﬂoating head will ensure no the number one target for new turf advised to reduce annual meadow- component in a turf grass sward. compromise on undulating surfaces. fungicides. It is not that long ago grass in favour of bent and fescue. It’s all about balance. when Fusarium patch would most Poa annua is even more suscep- SMART cassettes for ultimate turf 9 management

Designed for durability

www.charterhouse-tm.co.uk | 01428 661222 aerate brush de-thatch groom level mow scarify top dress

40 GI MARCH 2014 @BIGGALtd @BIGGALtd MARCH 2014 GI 41