Monthly Archives: September 2019

September 30th

Hi All,

It seems Mother Nature flicked the autumn switch pretty instantaneously this year. Only last weekend we were in the 20’s temperature-wise and enjoying an Indian Summer. Barely a week later and more than a ‘months worth of rain’ has fallen and temperatures are heading downwards, no bad thing for the latter though.

 Out walking yesterday, ditches had turned to rivers and brooks to torrents, some areas were totally impassable and truly I’ve never seen so much water at this time of year.  I also look at it as a wasted resource, all that energy going to waste.

And we aren’t done yet as more storms are lining up in The Atlantic to lash our shores with only a brief, cool / cold respite mid-week. Yesterday, my erstwhile colleague Dave Howells informed me of the latest Daily Express rant as Hurricane Lorenzo is set to track its way towards our shores at the end of this week and is billed as the ‘worst storm to ever reach the U.K’. (and Ireland of course)

Now if you read the graphic below it states that the probability of a 1 minute gust averaging >=39mph (62kmh for our European friends) is between 10-20%. Rather than show a path of destruction this graphic shows a decreasing chance of hurricane force winds. Now without wishing to do a Michael Fish (thanks Dave) it will be generate an Atlantic storm but it won’t be the same intensity as it stands today out in the South Atlantic unless something different from this happens between now and Thursday night. Currently the projection is for Lorenzo to actually miss the U.K and track north-west of us, a detail The Daily Express seems to have overlooked 🙂

Image courtesy of https://www.nhc.noaa.gov

One thing is true though in that we are seeing more violent storms and more intense rainfall events and these are and will have a profound effect on modern-day life. Let’s hope Lorenzo gathers force, steams easterly along the Thames and takes out The Houses of Parliament, no loss there in my mind.

Looking ahead we have a succession of Atlantic low pressure systems gathering after this one courtesy of a jet stream that dipped south last weekend and opened the floodgates quite literally to a westerly airflow. So let’s put some detail on this.

General Weather Situation

OK, so we start the week on Monday with a brief hiatus from the autumn storm season, note the word ‘brief’. Brief because we are already seeing a new rain front push into the south-west of Ireland on Monday morning. This is set to bring heavy rain to Munster and Leinster and by lunchtime this rain will be into The South West and most of Wales before briefly halting. So away from this rain front across the south-west of the U.K, expect a quiet cool start to the day with light winds, a heavy dew and lower temperatures than of late. By mid-afternoon, this rain front gathers momentum and pushes eastwards across the southern half of the U.K to give a pretty wet 2nd half of the day for most. That said it may not reach eastern counties till after dusk. Since this low pressure is southerly orientated, the north and Scotland will see a pleasant, autumnal day with light winds, mid-teen temperatures and hazy sunshine. By mid-afternoon, the rain will start to clear Ireland from the south-west as it moves eastwards. So mid-teens and windy away from the south / south-east for Ireland with temperatures down in the low teens under that thick cloud and rain.

Onto Tuesday and overnight that rain will have brought some heavy totals to Wales, The Midlands and East Anglia / Lincolnshire as it moves across the centre of the country. By dawn it should be drier over these areas but the rain front will then be pushing north into northern England and a second front will now be across Ireland so a wet start to the day here. As we move through Tuesday morning, these two fronts consolidate as the centre of the low passes across Central England bringing further rain to Wales and the southern half of the U.K, from The Pennines south. Scotland again misses the worst and Ireland should clear from the west through the morning to leave a drier 2nd half of the day.  The centre of the low will slowly move across the southern half of England through the 2nd part of the day, so a very wet end to the day here. Pretty pointless forecasting wind direction because it’ll depend on your proximity to the low pressure. It may be north-westerly, north-easterly or south-easterly 🙂 Similar temperatures, low to mid-teens for Tuesday and pretty average for the time of year. As skies clear temperatures will drop sharply on Tuesday night.

Wednesday brings  a cold respite, at least I hope it does because I won’t be able to get my trials out if it doesn’t 🙁 It may also bring a touch of ground frost in places as skies clear overnight and temperatures drop significantly. So Wednesday looks like a dry, cold and sunny day with a brisk to strong, north-westerly wind which will certainly remind you that we are now in autumn. As we progress through the day we will see cloud build from the west across Ireland and later, the west of the U.K as Hurricane Lorenzo looms, well what’s left of it anyway. So temperatures down in the low double figures on Wednesday across all of the U.K and Ireland with Scotland and the north of England / Ireland, cool in that northerly wind. A good drying day mind.

Thursday sees the next Atlantic storm in the form of Hurricane Lorenzo push into Ireland in time for the Kerry rush-hour maybe. By midday, the rain from that storm front is across Ireland and further east we will start to see cloud and the wind build. That said for most of the U.K, Thursday morning will be another cold, bright and possibly frosty in places start to the day before that low pressure moves in. So a wet morning for Ireland, drier further east. Now currently the worst of Lorenzo is expected to stay out in the Atlantic .

Here is a schematic of its current tracking as of Monday morning…

Images courtesy of Meteoblue, graphical arrangement courtesy of me…

Now storm paths and intensities can change so best to keep an eye on the local weather advice as we move closer to Thursday. Currently then as you can see we will see rain and strong winds move into the west of Ireland from dawn and this will push eastwards across The Irish Sea into the west of England, Wales and Scotland during the course of Thursday afternoon accompanied by strong but as currently projected, not hurricane force winds. If the storm path changes and it crosses the U.K, that’s a different matter. There Dave, a Michael Fish banana skin avoided…….So after a cold start for the U.K, cloud will swiftly move in and push rain across the country. Staying cool with temperatures across Ireland only in the low double figures maybe just nudging the teens further south.

Closing out the week on Friday and we see that rain band cross the U.K overnight bringing heavy rain in places, possible to The North East leaving us with a showery and breezy picture to finish the week. So Friday will see a showery picture across Wales and the west of England (particularly) interspersed with some sunny intervals with more of these further east. It will feel milder than of late with temperatures nicely up into the mid to high teens across the southern half of the U.K. So a good drying day between the showers on Friday but always we have the risk of a new rain front lurking out in The Atlantic. This is currently projected to make landfall into West Ireland around midnight on Friday and will bring heavy rain across Ireland for Saturday I’m afraid.

So how are we looking for the weekend ?

Well I think it is very much a west-east divide with Ireland, Wales, The South West and western coastline of the U.K stretching all the way up to north-west Scotland in line for some pretty heavy rain on Saturday. This rain front is projected to move eastwards leaving behind a showery picture over Ireland and the west and bringing further rain to central and eastern areas of the U.K for the 2nd half of Saturday. The wind will be fresh to strong and from the south-west and so it’ll continue the mild feel to the weather. Sunday looks like a sunshine and showers day with lighter winds and a slightly cooler feel to the weather.

Weather Outlook

So how is the outlook for next week shaping up ?

Well next week looks to start as this week is projected to finish, that is wet and pretty windy with rain moving through on Monday. Tuesday and Wednesday look milder and a ‘sunshine and showers’ type scenario, particularly in the west with a strong westerly wind before a deep low looks to affect the north / Scotland on Thursday with very strong winds and heavy rain. Further south we pick up some much milder weather so it looks drier and warm with a strong wind for the latter part of next week, still with some showers feeding into the west, but most of them northerly biased. The weekend of the 12th October sees Saturday continue the sunshine and showers theme before it turns cooler with the wind switching round to the north. This heralds the arrival of an Atlantic high pressure to bring a northerly theme to our weather so that’ll be much cooler with night frosts and a cold wind. Plenty of time for this to change yet though.

Agronomic Notes

Well quite a lot to talk about since I haven’t been able to publish my blog for a few weeks. Most of it is unfortunately disease-related 🙁

Microdochium nivale activity

For some the Microdochium nivale season has started early with the end of the dry spell signalling an increase in humidity and dew levels and hence disease. Initially the north and west of the U.K and Ireland picked up the rain whilst the south and eastern counties stayed dry. So this meant that for Ireland, Wales, the north-west and Scotland we saw increased Microdochium activity from the 3rd week of August onwards. For the south of England, Wales and eastern areas we had a couple of weeks of grace before the same set of conditions transpired to promote quite aggressive disease activity particularly towards the middle of September.

Warm, humid overnight air with very little wind (and hence dry down of a wet plant leaf) are the optimum conditions for autumn Microdochium nivale and so we often see more aggressive attacks at the start of the season on sheltered turf surfaces with less air flow. This is quite different from later in the season when the exact opposite can be the case.

As some of you will know I’m working hard with my colleague, Paul Vipond, on a disease prediction model for Microdochium nivale and it’s definitely a case of the more you know, the less you understand 🙂 That said we are making progress and it allows me to put up some graphical information showing how disease severity has panned out during September in a number of locations. It also shows the difference in disease pressure between a sheltered and open site scenario.

Here’s a taster from a few locations, sorry the bottom scale is small but it can’t be avoided ;

So you can see a much higher level of predicted disease on the sheltered sites within a location as opposed to more open sites. This has proved to be the case in practice but of course other variables come into play like surface organic matter content which cannot be forecast in a disease model.

Here’s a great proof of the pudding shot taken at the end of last week…

The majority of the Microdochium on this green was in the shaded environment which was likely to have had dew forming on it for longer. Throw in some nights when the air temperatures stayed up above 15°C and there you have Microdochium.

That said I did see some shaded greens last week with much lower level of M.nivale compared to more open, higher surface organic matter examples on the same site. This level of disease is I think typical of a badly hit golf green currently ;

Now ordinarily you might be reaching for the fungicide when you see such a level of active disease but even that has been a bit of a quandary hasn’t it ?

This cropped image from Weathercheck highlights the 3 main issues with combatting disease during September, 2019.

They are of course ;

  1. Very high growth rates that limit the longevity of a fungicide and any other liquid application.
  2. Very high daily rainfall totals that risk washing product straight through the profile soon after application.
  3. Windy, unsettled conditions that make finding a spray window tricky.

Now of course there’s two sides to every coin and that high level of daily growth that limits product longevity will also mean that the scars from these early Microdochium outbreaks will be grown out quite quickly. The more your surface organic matter is where it needs to be % wise, the quicker that process will take place. Wet and windy weather also doesn’t tend to encourage high levels of disease activity because that weather dynamic is very different from dew formation in terms of plant leaf wetness and possibly other parameters.

It isn’t just Microdochium nivale that has been evident, we have also seen some very aggressive Red Thread and Leaf Spot out there on high Fescue / Ryegrass swards because of the combination of humidity and temperature.

Looking ahead…..

Now some of you out there may not have applied a fungicide and may not have needed to either because of the climatic conditions on your site and other variables I’ve already eluded to.

We do know that October normally represents the highest incidence of Microdochium nivale inoculation that we will experience across a season but not the only incidence as last year proved with aggressive new Microdochium outbreaks in late November and December.

For this reason one of my concerns going forward is getting a spray window to apply any liquid application be it fungicidal, non-fungicidal or nutritional. Looking at this week, Wednesday seems to be the only day when the outlook is pretty dry and wind speed reasonable. Thereafter it becomes much harder to spot a window at all for the next 7 days particularly in the north and west.

Crane Flies…

A lot of these guys around at the moment and there have been for the last 10-14 days in my neck of the woods. Syngenta’s Turf Pest Tracker provides a good update on regional variations and intensity of hatch (you can find it here)

My hobby of fly fishing also helps in this respect because Trout really turn onto Daddies as we call them when they are in abundance.  Out on the beautiful Eyebrook reservoir recently one of the old lads pointed to a tractor working the fields close to the reservoir. “He’ll be stirring up all the Daddies, that lad will, worth a try I think” he remarked. As usual he was right, there’s a lot to be said for experience 🙂

It got me thinking about the timing of late season aeration and the fact that many areas are seeing Crane Fly laying eggs at the moment and if you have greens with open hollow / sold tine patterns , that presents a perfect incubation site for the Crane Fly. We are all familiar with the chamfered tine hole edge indicative of the nocturnal chomping of a Crane Fly larvae and if your greens have open tine patterns, it is a perfect opportunity for them.

A good argument for late summer rather than late autumn aeration maybe, pushing recovery and getting things put to bed before the end of September ?

Ok that’s me for now, apologies for the hit and miss nature of the blog of late, it is I can assure you unavoidable.

All the best.

Mark Hunt

 

 

 

9th September

Hi All,

First up my apologies on the lack of blog last week. I am afraid this will be a pattern from now on as other matters take precedence. I will do my utmost to keep some form of consistency especially as we move from summer to autumn and Microdochium nivale rears its inevitable head.

In the flash of an eye seemingly we have moved away from summer to early autumn, with the nights drawing in fast, the harvest completed and some chilly mornings not far short of a frost lately. Sunday morning we were down to 2.2°C. We will though I think enjoy an Indian Summer this September so don’t put away those shorts and sun cream just yet eh…

Sept 15th, 2019 projected jet stream path – www.Tropicaltidbits.com

I was reading in New Scientist the other day about some suggested schemes to re-ice the Arctic in the hope of avoiding the climatic Armageddon that is currently heading our way. One part of the article looked at why losing ice from The Arctic is so bad and of course one immediately thinks of rising sea levels and the risk of more coastal flooding. One of the other points made was a growing weight of evidence that the warming Arctic is affecting the behaviour of the sub-polar jet stream, the one that gives the U.K and Ireland its ‘particular climate’.

The article explained that with less temperature difference between the Equator and The North Pole, there appears to be less energy driving the jet stream and so it forms into the meanders (Rossby Waves) that I’ve been talking about for the past 10 years or so.

The best way to think about this is looking at a river from a bridge. In mid-current the flow rate is strong and straight with very few meanders but as you come to the side where the bank shape affects the flow, you’ll see a slower flow rate and meanders / eddies in the current. This week coming we see a ‘peak’ pattern forming in the jet stream where its flow is slowing down and warm air is pushing up from Africa.

Did this happen 100 years ago ?, who knows ? because we’ve only known about the existence of the jet stream since the mid 1940’s and to this day we understand very little about the complex mechanics that creates its pattern and speed. Ultimately this is why we cannot predict the weather further than 10 days away so please don’t ask me how winter 2019 looks 🙂

General Weather Situation

Sitting at my desk on a drab, grey Monday morning, it looks far from an Indian Summer outside and on the rain radar bands of rain that crossed Ireland overnight are now orientated vertically across the U.K and slowly moving eastwards. So if you are dry, you may not stay that way for long. There’s some particularly heavy rain crossing Wales currently and that bring flooding to some areas. So Monday looks a wet one for the U.K but across The Irish Sea you look better with just some showers pushing in off the west coast likely this morning. This rain is slow-moving and so expect showers and thick cloud for most of the day only clearing in central and eastern areas later this afternoon with a likelihood of the rain persisting across the south coast, The South West and Wales till dusk. On the cool side as well with only 14°C likely under that thick cloud and rain. despite a southerly orientated wind.

Onto Tuesday and the rain has cleared overnight to present a largely dry picture, dull as well but low pressure isn’t finished with us yet as another pushes in from The Atlantic. Now the projections are for it to sit out off Connacht tomorrow morning so the U.K and Ireland look to have a dry morning / afternoon but as we approach the late afternoon, the rain makes landfall in north-western Ireland and pushes across country. So dry with some cloud cover breaking across the U.K through Tuesday morning, staying cloudy across Ireland and Scotland with rain pushing into north-west Ireland late afternoon Tuesday. During the course of Tuesday evening that rain pushes across Ireland and into north-west / west Scotland with some heavy rain bursts for the north-west of Scotland. In the wee hours it’ll be across Ireland, Scotland and pushing down into North Wales and northern England. Despite the threat of rain on Tuesday for Ireland, the U.K will enjoy a warmer day with temperatures pushing up into the high teens with some hazy sunshine and cloud. Winds will be light and from the north swinging southerly later.

So by dawn on Wednesday that rain has cleared Ireland save for some showers over the tip of Kerry. It’ll be spread in a line down the western half of the U.K, across northern England, The Midlands, Wales and The South West. So East Anglia and The South East will enjoy a dry start to Wednesday but it probably won’t last. So through the course of Wednesday morning that rain will move south and east clearing Scotland and the north / west of England as it does so. Expect there to be some showers over north-west Scotland throughout the day. Ireland with that rain long gone should enjoy a largely dry day with temperatures picking up a bit from their recent low’s to mid-high teens. Warm in the south of England as well in-between that rain with temperatures sitting in the high teens.

Onto Thursday and a north-south divide presents itself with rain pushing over the north and west of Ireland through Thursday morning with the south staying mainly dry. That rain will soon be into the north-west of England, Western Scotland and during the morning will push eastwards across Central Scotland. So for southern and central areas of the U.K, Wednesday should be dry and getting warmer as high pressure nudges up from the south. Temperatures should be in the low twenties I think for these areas with Ireland in the high teens away from that rain and mid-teens for north and west Ireland and Scotland. So a wet day for north and west Ireland but as that rain pushes eastwards, the sun follows it and temperatures pick up nicely for the 2nd half of the day. Windier on Thursday though with a strong south-westerly – westerly wind coming to play.

Closing out the week on Friday and high pressure is very much in charge with clam and settled conditions over U.K and Ireland. A much milder night will give way to long spells of sunshine and temperatures picking up into the low twenties for England and Wales. Ireland and Scotland will be a bit cloudier and that’ll keep the temperature down in the mid-high teens but crucially dry. Winds will be light and from the north.

With high pressure asserting itself and pushing warm air northwards the weekend looks to be fine, dry and settled with plenty of sunshine, light winds and temperatures up in the high teens / low twenties. Just as well then as I’m off for a week 🙂

Weather Outlook

So will The Indian Summer remain in place for next week ?

Well the short and sweet answer is yes, next week looks like high pressure calls the shots so that means cool nights, heavy dews, warm days and plenty of sunshine. I expect day time temperatures around 20°C for England and Wales and 18-20°C for Ireland and Scotland. By the end of next week the high pressure looks to be pushed eastwards by a north-west Atlantic low pressure so we could see things break down from the end of next week.

Agronomic Notes

Since this is my first blog of September, we will of course have a look back at the previous month and see how the land lies. Very much a north-west – south-east divide though, especially when it comes to rainfall with some areas very dry for the month, others excessively wet.

GDD Summary – August 2019 – Location – Thame, Oxfordshire, UK

Interestingly, August 2019 came out almost identical to August 2018 when it comes to GDD and ranks as one of the warmest August months for this location. When you look back at the previous years figures you see remarkable consistency in the total GDD value on the hotter Augusts. 2013 came in at 360.5, 2016 at 364.5 (identical to 2019), 2018 at 362 and 2019 at 364.5. 3 of the last 5 years have come in with a very hot August from a temperature perspective at this location. I know that it will be very different at more western and northern locations. Remember I said 2019 was tracking in a very similar fashion to 2016 a few months back ?, well there’s your proof.

Overall for the y.t.d, GDD-wise we are tracking behind 2018 and 2017 courtesy of that much cooler (and wetter) June we endured this year. That period of weather has had consequences from an agronomic perspective, some of them good, some of them bad.

G.P / Rainfall Stats – U.K Locations – August 2019

During August we saw a north-west vs. south-east divide across both the U.K and as you’ll see shortly, Ireland. The main rain fronts affected the north and west of the country and so these areas ‘enjoyed’ a cooler, wetter August vs. south and east where it was both warmer and drier. The Bristol and Fife locations back this up with ≈ 150mm of rain for the month. Growth-wise as measured by G.P there’s similar variability with the wetter locations lower as expected.

Looking at the Irish locations we can see similar variability albeit much wetter than the west and north of the U.K. So the west and north-west side of Ireland endured a very wet August with over 8″ (200mm) whereas the east side was 45-50% lower from a rainfall perspective. GDD-wise, any month when you’re recording > 250GDD means if you had rainfall, you also had significant growth. Donabate, north of Dublin came out with the highest GDD figure and 164.6mm of rain so I imagine keeping on top of growth there was tricky in August.

I find it sometimes difficult when you look at the variability between locations in the U.K and Ireland to write a ‘one-size fits all’ sort of blog because on one hand you have a very wet and cool August vs. a warm and pretty dry one elsewhere. Some courses will be more concerned about flooding whereas others will be experiencing a continuation of our dry (ish) summer. Looking back at last August I can see a similar picture with drier conditions across central and eastern areas and much wetter conditions across the north and west.

Disease Activity – Take All

Late summer this year has shown a high level of Take-All activity on a lot of surfaces and not just affecting Bentgrass either. I’ve seen it on greens, collars, approaches and tees and it’s been taking out Bent and Poa annua. as well. No why should this be ?

Well to answer that question we have to go back a few months and look at June 2019’s weather pattern.

Looking at the very nice chart created as part of the 2019 GDD / G.P spreadsheet, you can see a pronounced dip in the early part of June from a G.P perspective and that’s because it was cool. We also see some pretty heavy rainfall lasting for 7-10 days. It was this climate dynamic that has led to increased Take All activity this summer.

Take All as a pathogen is usually active in a cool, wet spring, typically between March and April, attacking the root system of its chosen host plant. Symptoms however do not show until the plant goes under E.T stress during the heat of summer when it needs to uptake more moisture through its roots. The damaged root system is unable to uptake sufficient moisture to replace that lost by E.T and so the grass plant shows symptoms of wilting and die-back in a characteristic ring-like pattern. The above scenario is normally only an issue on new constructions in their early years and typically it is a Bentgrass-only pathogen.

When we have a wet summer though this cycle seems to repeat itself and so with the cool and wet June period of weather I think the pathogen was active on Poa and Bentgrass roots, but symptoms didn’t show until we experienced some drier, warmer weather during late July and August (depending on your location)

So if you’ve seen some die back in rings this summer, it is likely to be Take-All disease and for myself, other than rubbing in some chitted seed and rootzone into the patches, I think you’ll see it grow out under favourable agronomic conditions.

Microdochium nivale

I am wondering looking at the stats for the north and west whether those locations saw increased Microdochium nivale activity during August with the long periods of plant leaf wetness and mild temperatures. For sure as we approach mid-September our thoughts turn to controlling this pathogen and the two hard previous autumn conditions we have endured.

This autumn I am guessing most of you will have stock of Propiconazole-based formulations if you purchased before June’s revocation date and so in terms of control products will be in a similar position to 2018.

It’s not until next autumn that we move into a position of relying on fewer chemistries with (hopefully) some newer ones as well. Some of you out there I know will be trying to control this pathogen without applying a fungicide instead relying on a good non-pesticidal IPM regime, so by the time we get to spring 2020, it’ll be an interesting exercise to reflect on the weather patterns and disease activity that we experienced and how effectively you controlled it.

Certainly autumn / winter 2018/19 taught me two key lessons ;

  1. Getting to Christmas with a clean sward doesn’t mean you’re over the hump of Microdochium nivale activity
  2. Plant leaf wetness plays a significant role in the development of this disease and perhaps is more significant than just air temperature alone.

Ok that’s the blog for this week, next week I am having some time off so I’ll catch up with you all on the 23rd September.

All the best.

Mark Hunt