Monthly Archives: September 2017

September 25th

170925_gfs_pres_500p_loop_eur

Hi All,

After a simply beautiful autumn day yesterday when the temperature topped 21°C and the sun shone, it’s now back down to reality with my projected ‘unsettled start to the week’ coming to fruition.

Autumn is very much in progress and already some of the trees are changing hue. You get some simply beautiful colours at this time of year kicked off by the combination of cold nights and bright days…Saw this amazing Virginia Creeper growing up the wall of a house in Hallaton. The image is a bit blurry because I didn’t want to stop walking and take the picture thereby detracting from my mile average speed…ok, ok I admit it, it was because The Hare Pie Cafe was just around the corner and an imminent Latte and Flapjack beckoned :)_

vircreeper

That predicted low pressure in The Bay of Biscay is feeding up heavy rain from south to north and that’s making some peoples Monday morning start a very wet one indeed……21.1mm so far today and that’s roughly double what was forecast….reckon we will top 25mm  by the time the morning is over….:(

250917 Sept25th17

 

 

 

 

General Weather Situation

Ok so we know the central part of the U.K is starting off very wet today on Monday in a line stretching from the south coast right up to The Shetlands, there are some gaps in that rain band and either side of it as well. Through the morning we can expect that rain to stay in situ and then gradually fizzle out. You can see from the rain radar that Ireland is totally clear and here you can expect a beautiful autumn day with temperatures in the high teens but treasure it because you won’t see many more dry ones this week :( Wales and The South West will also stay largely dry with nice temperatures as well as will the western side of Scotland. Under that rain expect mid-teen temperatures only. By dusk the rain has all but gone except for a persistent area over Central Scotland which will last through the night I’m afraid. Winds will be light and easterly making that rain slow moving.

Onto Tuesday and a much better day for one and all with only that rain over Central Scotland (east I think of the A9) hanging on first thing. Through the morning that cloud cover will thin to give some pleasant spells of sunshine over most of the U.K and Ireland. In that sun, temperatures will push through to the high teens and I can see it being dry for the entire day but like I said enjoy it because it won’t last this week…Again winds will be light and from the east.

Overnight into Wednesday and the first of those Atlantic rain fronts has pushed into the west of Ireland and brought heavy rain to the west of Ireland. This front will be slow-moving so expect rainfall totals to be high across the west and central Ireland as that rain moves from west to east. I wouldn’t expect it to hit the east of Ireland until lunchtime. By mid-afternoon that rain front is expected to push into The South West and West Wales but won’t reach South Wales and the M5 till later on Wednesday night. So Wednesday looks to be another dry day for most of the U.K and certainly central and eastern areas will stay dry right through till Thursday morning when that rain front is expected to continue its eastern march. So wet for Ireland but a pleasant day for the U.K till that rain arrives in the west with similar temperatures to earlier in the week. Windier on Wednesday with a strong to moderate south / south easterly wind.

Onto Thursday and overnight that rain front is expected to push across the U.K bringing rain to the north of England and Scotland in particular in time for the morning rush hour. It may just break up over The Midlands leaving a dull but dry start here for Thursday. Ireland should have a much better day after that heavy rain on Wednesday with some spells of sunshine across the west in particular but expect a new rain front to push in by late afternoon / early evening.  Through the morning that rain and thicker cloud will push away to the east to leave brightening skies and better conditions behind with a much better end to the day everywhere across the U.K. During the evening we can expect a new rain front to push into West Munster and cross Ireland overnight bringing more rain to already saturated soils. As that sun breaks through across the U.K after the early morning rain and cloud I would expect pretty reasonable temperatures up in the high teens again with only mid-teens across Ireland and Scotland due to the thicker cloud cover.

Friday already and if only a work week could pass as quickly as I type it on a Monday morning..ho hum. So a cloudy start for the U.K and that vertical rain band should be sitting across the east of Ireland before moving off into The Irish Sea during the late morning and moving into Wales, The South West and the western coastline of the U.K by early afternoon pushing cloud cover ahead of it. So that makes it a duller, cloudy day on Friday with rain arriving for the 2nd part of the day across central and eastern parts of the U.K clearing behind it as it goes. Winds will be moderate and from the south.

So how does the first snapshot of the weekend look sitting here on a dull and damp Monday morning with the rain gauge edging past 23mm as I type ? Well for Ireland, Wales and the west I think Saturday could be a pretty nice day with that rain band predicted to affect the eastern side of the U.K during Saturday morning and it may hang on for most of the day across East Anglia. So sunshine and some scattered clouds expected west of that rain but we can expect a wind change on Saturday to westerly so that’ll take the edge off the temperature with only mid-teens likely I’m afraid. Sunday looks like being a reverse of Saturday with low pressure pushing rain into Ireland and this rain may move south eastwards so possibly only affecting the south of England through Sunday.  Winds will be back to southerly again so a little warmer on Sunday and away from the risk of that southerly / westerly rain, another pleasant day I think.

Weather Outlook

So here’s my prediction for the start of next week….extremely windy…..

gfs_500p_7d_eur021017

As you can see from the GIF above for next Monday we will have an intense low pressure system hanging over us and I think I’m right in saying this one is going to be called ‘Brian’. So yes it looks like Storm Brian will have you hanging onto your hats at the start of next week two weeks after the last storm (Aileen). So Monday looks like being wild, wet and windy and that pretty much sets the tone for the week really with the winds turning to a cooler, north westerly by Tuesday and that means the focus of the rainfall will also be more north westerly for Tuesday before switching round to the south west again for Wednesday and bringing that rainfall more south and westerly from Wednesday onwards. So next week looks windy, wet at times and mild (ish) with absolutely naff all spray days…

Agronomic Notes

CraneFlylaying

Out walking yesterday across Leicestershire and noted loads of Crane Flies coming up from the grass at my feet suggesting that there could be high pressure from Leatherjackets over winter and particuarly next spring.

The situation with insecticides continues to be a common theme on my travels (alongside Carbendazim) as currently we don’t have an effective control method. I may be wrong but I think with insecticides we will see something come to the market in the future, when I’m not sure but if you consider that the whole of the agricultural market is up for grabs to whoever can develop a product then that’s a big prize in terms of £’s and hopefully we can hang onto their coat tails and gain an approval for amenity.

Someone once said to me that legislation and logic don’t sleep in the same bed together and insecticides seem to be a classic case of this. It’s all down to registrations and of course the E.U’s thematic strategy for pesticides, you know that wonderful piece of legislation from the European Union (one of many) that is currently making all of our lives tricky in the amenity market.

It’s wrong of me of course to bring this up because at least it’s the same for every country in our climatic zone isn’t it…isn’t it ?

Well no it isn’t….:

Under the regulations above there’s a system called Mutual Recognition that is supposed to facilitate faster and more efficient registration of an active substance in one country with another, provided they are in the same climatic zone.

We are in Zone B Centre.
The following Member States belong to this zone:
Belgium, Czech Republic, Germany, Ireland, Luxembourg, Hungary, Netherlands, Austria, Poland, Romania, Slovenia, Slovakia, United Kingdom

Strange then that whilst the U.K turf industry has no insecticide, The Republic of Ireland still has Merit, the German Golf market has access to an insecticide from Syngenta called Karate Zeon and I think the Austrian market also has insecticides available ?

So how does Mutual Recognition work ? (not well I’d say)

Surely the parameters for consideration are the same in the U.K golf market as the Irish or the German or the Austrian turf market ?

You can read about the legislation with respect to climatic zones and mutual recognition here

Disease pressure remains high….

DiseasePressure25092017

With 3 warm nights out of the last 7 and the higher night time temperatures coinciding with periods of high humidity, it is no surprise that our association with high disease pressure has continued for another week. It isn’t just about night temperatures either because currently as I sit and type this it is 15.1°C and 100% humidity.

This combination of conditions will tip the balance very firmly in favour of disease development even if you have an effective fungicide applied. Most modern-day fungicides should really be called Fungiostats which broadly intepreted means that they slow down the growth of the fungal population rather than killing it outright. When climatic conditions are driving the fungus to reproduce faster than normal (as they are currently and have been for awhile) then that’s when you will see active disease even if you have sprayed recently with an effective chemistry and allowed it time to be taken up into the plant….

What’s the outlook for the rest of the week ?

Looking at Meteoblue’s forecast for the coming week it looks to me like we will see continuing high disease pressure over the next 48 hours with both Monday and Tuesday night fitting the scenario of high disease pressure.  Thereafter we will lose some night time temperature and that should reduce the disease pressure a little until the end of the week when it’ll decrease further. Fortunately for most of the U.K, you’ll have some good spray windows.

More Yellow Turf than I’ve ever seen at this time of year..

YellowTuft

I’ve seen more Yellow Tuft on my rounds this year during September than I think I’ve ever seen. Yellow Tuft (Sclerophthora macrospora) is a disease of prolonged cool and wet conditions and more usually in my experience occurs later into the autumn / winter. The yellow blemishes are individual affected plants and these can develop shallow rooting and excessive tillering making them easy to detach from the turf surface.

If you are seeing this disease on a particular turf area it’s worth checking to see if that area has more organic matter (and is therefore perching water) and / or there’s a potential issue with water movement further down the rootzone. (High level of fines, silt or clay possibly in the rootzone). There is (to the best of my knowledge) no labelled fungicide that shows effective control (in this country anyway) so the solution is more cultural and weather-dependent.

Ok that’s it for this week.

All the best for the coming week and prep wisley for Storm Brian if it turns up :)

Mark Hunt

 

 

 

September 18th

170918_gfs_pres_500p_loop_eur

Hi All,

I was reading New Scientist this weekend in a rare moment of calm and they had an article on the latest U.S Super-Storms that have hit the Southern United States and the ongoing debate as to whether they are caused by Global Warming. Now Hurricanes are a natural feature of the weather and seasons in that part of the world so their occurrence certainly isn’t but their neHarveyw-found strength is linked to abnormally warm water in the Gulf of Mexico and a unusually slow storm path wherein the weather system gets stuck in place dumping high levels of rainfall over short periods. Sound familar ? Both of these features are implicated as a consequence of our warming world…..Good job Trump demonstrated good future vision by rolling back all of Obama’s Flood Defence Protection initiatives just days before Hurricane Harvey struck. You can almost imagine Mother Nature giving Trump (dressed as King Canute) the finger….wood

I’ve also been busy working on my garden and I was amused to see this label stuck to the top of a wooden stake I was using…….Judging by the ingredients of the wood treatment, I think there might be a nice little earner in hanging around wood yards and buying some treated wood chip :)

Ok onto the weather and is that Indian Summer making an appearance or are these strong Atlantic low pressure systems putting paid to that idea ?

General Weather Situation

So for Monday we have a somewhat messy weather picture with low pressure from last week sitting over Europe, another one north west of Scotland and high pressure squeezed in-between. Now this scenario will settle the weather for a few days but that high pressure won’t dominate I’m afraid so expect change as we approach the end of the week, but it’s not all bad news…..As inferred last week, the north and east are likely to pick up some wet weather this week due to the proximity of the low pressure system over Europe. So today we have a relatively calm and dull start to the week. That thick cloud layer over the U.K and Ireland will break up to give a nice sunny day with pleasant temperatures. Across the Irish Sea we may see some rain creep into North Wales, The North West and East Anglia by late morning and this will be joined by some thickening cloud later in the afternoon over Scotland, the north of England and Wales. By the evening this rain sinks southwards into The Midlands before fizzling out. So a mixed start to the week and temperatures where you’d expect to see them of late, mid-teens, held back by that light to moderate northerly wind.

Onto Tuesday and again a dull start for us all but that cloud cover will soon break to give long spells of sunshine over most of the U.K, with the possible exception of some rain brushing the coastline of East Anglia again. Through the morning Ireland will see thicker cloud across the west, but pleasant sunny intervals along the east coast. By the afternoon, this thicker cloud over Western Ireland converts into rainfall which pushes cloud and rain across all of Ireland for the 2nd part of the day. The U.K looks to stay largely dry all day Tuesday and with light winds shifting round to the west, we will pick up a degree or two temperature to hit the heady heights of the high teens in some places 😛

Mid-week beckons and that rain over ireland pushes across The Irish Sea overnight to grace the north of England and Scotland with its presence. Menawhile a new rain front of potentially heavier rain is set to make landfall around dawn on Wednesday in Kerry and bring heavy rain to the west coast and Midlands of Ireland. The U.K looks to have a dry morning until that western rain pushes into Scotland and West Wales by early afternoon with Wales, the north of England and Scotland in line for the worst of it I’m afraid. Further south we look to stay dry for most of the day as that rain stays more northerly. Much stronger winds on Wednesday and from the south west so mild everywhere with mid to high teens again the order of the day.

Onto Thursday and that rain overnight has formed a vertical band straddling The South West, Wales and the west coast of the U.K, expect it to be potentially heavy. This band of rain looks to straddle the M5 for most of the day so if you’re driving up or down that motorway, take care on Thursday. West of that band of rain we look to have clearing skies and a predominantly dry day for Ireland and Scotland, though the far north east of Scotland may pick up some heavy mizzly drizzle. Sunny intervals for Ireland but thicker cloud will give a dull, cool day for Scotland though this is expected to clear from the west in the afternoon. By dusk that rain band has drifted east and south and is expected to lie from Bristol diagonally up to The Humber crossing The Midlands, so south of this line should stay reasonably dry but predominantly cloudy. Strong to moderate south westerly winds again for Thursday and mid-teen temperatures maybe pushing up into the high teens in the south of England.

Closing out the week on Friday and we have a dry sunny start across Ireland and the U.K but it won’t last for the latter because by early afternoon a rain front will push into the west of Ireland and rapidly move eastwards crossing Ireland during the mid-late afternoon. For the U.K we have a really nice autumn day with light winds and plenty of autumn sunshine so a cracking end to the week here with long spells of sunshine expected with maybe more in the way of cloud across Scotland. Temperature-wise I’d expect low to mid-teens across Ireland under that thicker cloud and rain and mid to high teens for the U.K depending on cloud cover.

So how does the weekend look ?

Well we have high and low pressure battling it out but this time the high pressure is out on The Continent so it’ll shift the wind direction eastwards and that should keep the deep Atlantic low pressure system lying north west of us out of the picture. So a nice dry weekend beckons with light easterly / south easterly winds and plenty of sunshine. (There you go Mr Collins :) )

Weather Outlook

So a settled weather picture to start next week ? No not really as we have a sneaky low forming in The Bay of Biscay and that might bring rain across the south west and south coast of the U.K for the early part of the week. Tricky to say at this stage because it really depends on the behaviour and position of this low pressure. If it’s close to the south coast of the U.K then we can expect unsettled weather for the south of England but drier for the north, west and Scotland. At this stage I think we will see some unsettled weather at the start of next week but it’s likely to be more south and east of the U.K that is affected. With strong south easterly winds in place we should retain some decent temperatures. By mid-week we have a deep Atlantic low coming in and it is a cool one as well (the first time I’ve seen blue on Unisys for awhile) and that looks to bring unsettled conditions with potentially heavy rain into Ireland for Wednesday before crossing the Irish Sea into Wales and the rest of the U.K from Thursday onwards. A wet end to the week then possibly with strong south westerly / southerly winds I think.

Agronomic Notes

DollarSpotmycelium

Dollar Spot

There’s been a lot of Dollar Spot about this season, both here and on the continent and undoubtedly the driver is the wet summer, high humidity and extended periods of plant leaf wetness. It tends to affect tees, fairways and approaches here more than anywhere else rather than greens but I know this is different on the continent with more fine turf areas affected.

There may be a number of contributing factors as to why higher height of cut areas are affected more but I think one of them is related to plant leaf wetness. I think it is likely that on the areas affected, the plant leaf stays wetter for longer because most courses don’t physically remove the dew off fairways (although some do with late season tournaments). It’s also related to improved plant health on greens vs. fairways and possibly because we are already applying fungicides on greens for Microdochium control that will also control this pathogen. Saw a classic case of this last week on approaches and you can see the line of demarcation quite clearly between good nutrition combined with a light rate fungicide vs. untreated…

DollarSpot.JPG_Ox

Growth Patterns – September to date…

SeptTempGP

We have had some pretty chilly nights over the last week or so courtesy of a strong northerly airstream and you can see from the chart above that we touched close to 5°C on Friday and Sunday during the night. That knocked the Growth Potential right down (as well as triggering my central heating to come on unexpectedly…”In September ?, Not on your nelly !” says me….) from its near optimum of the week before and hopefully allowed you to get on top of grass growth on outfield areas in particular. That’s quite early in my mind for the temperature to drop this low but its worth thinking about the consequences of this looking at the week ahead.

Obviously greens growth will have dropped off with this sharp reduction in temperature and that brings me onto the perennial debate concerning PGR usage late in the season and the pros and cons of this. Obviously one of the key areas going forward is PGR usage with respect to increased fungicide efficacy, it is a logical thought process in my mind that if a plant is regulated going into the autumn (and particularly during October) then it will extend fungicide longevity. Of course every coin has a flipside and if you have active disease and you have regulated your grass plant then it will be slower to grow out, this is also logical and one of the reasons why some foliar pathogens are more aggressive on grass that has been treated by a PGR.

There’s also the question of combining a PGR and a fungicide in the same spray tank. I know a number of people do this with apparently no issues in terms of phytotoxicity (plant yellowing), but what about efficacy ?

How do we know that a joint application of a PGR with a systemic fungicde (specifically) doesn’t affect the rate of uptake and efficacy of the latter ?

To add further to factors that we have to consider, we know that one family of fungicides in particular, the DMI’s (Demthylation inhibitors), which include Propiconazole, Tebuconazole, Difenoconazole exert their own plant growth regulatory effects to varying degrees, with some actives more regulatory than others. So by applying a PGR with a DMI we do have the potential to cause some yellowing of the plants within a sward and specifically annual Poa annua biotypes. I’ve looked for some research on this subject and found quite an interesting example on this link – http://turf.unl.edu/turfinfo/July9%20PGR%20Over-Reg.pdf

For me I think it’s something an end-user can evaluate very easily in the field themselves on their surfaces by trialing an extension of PGR usage up to the end of October on say 9 greens / tees (because disease on tees last autumn was both aggressive and common) or half a sportsfield vs. untreated.

Why up to the end of October and not beyond ?

GPAutumn

Well in a normal autumn we tend to have a sharp drop off in growth from the beginning of November (usually after a balmy Halloween with high disease pressure) and often the combined growth during November and December isn’t equivalent to October on its own from a GDD and G.P perspective. So there’s a strong argument that Mother Nature does the job from November onwards though in 2015, there’s a counter-argument that you could have continued PGR usage right up to Christmas such was the extent of the mild weather !

It is without doubt a complicated debate with as many pro’s as con’s but it is an important one as we look to develop and improve disease management strategies in the light of the loss of effective fungicide chemistries and the arrival of lower A.I-content replacements.

The week ahead…

G.PSept1817

So looking ahead at this week you can see that the cool northerly winds are keeping the G.P / GDD down in the early part of the week but as the winds lessen and change direction we pick up some pretty good growth at the end of the week / weekend. So if you have spray windows I think it’s a good time to get your last hit on weeds prior to the onset of autumn proper. Picking up greens with foliar nutrition will also be beneficial provided you have gaps between the rain (more of an issue for Ireland and Scotland this week I think) . Overseeding of thin / worn areas from the summer will also continue to be effective as we look to keep good air (and therefore) soil temperatures through the latter part of September as per usual.

Ok that’s me for another week.

All the best…

Mark Hunt

September 11th

170911_gfs_pres_500p_loop_eur

Hi All,

Last week I signed off with the comment that I had a bitch of a week coming up. I guess it’s a measure of my forecasting prowess that a little more than 5 hours later I was heading over the bars of my mountain bike at 20 mph with a heavy and painful landing to follow. A bitch of a week then followed so in this respect I can say my forecast for last week was 100% accurate even though it may have had not a lot to do with the weather :)

With high pressure out in the Atlantic and low pressure sitting in a cold air trough over us, it’ll definitely feel like autumn this week. As commented on previously, this combination of weather systems drags cold air down from the north and that always takes the temperature downwards.

Out walking yesterday it was notable to me that the hue of the countryside  has changed since my last walk with the gold of crop fields now changed to earth brown with lots of ploughed fields already sowed for next year. Skimming low over them were flocks of young House Martins and Swallows feeding up before they disembark to warmer climes for the winter, no doubt gorging themselves on the numerous Daddy Longlegs that I could see. So must we prepare ourselves for autumn and perhaps not the most favourite time of year for greenkeepers and groundsman alike as leaves, worms and Microdochium move up the things-to-sort list :(

So are we staying unsettled or do we have any hope of an Indian Summer ?

General Weather Situation

So kicking off Monday we have a raft of showers moving on a west to east trajectory with some heavy bands already present across south west Munster, Connacht and Donegal. For the U.K we have a particularly heavy belt moving along the M4 / M25 stretcbuffhing from Bristol to Kent so this will be a feature of your day here I think. Further north we have heavy showers over mid and North Wales, The Pennines and The Lakes and a heavy rain front over central and eastern Scotland.  As we go through the morning we will see further showers crop up and push eastwards across all areas of Ireland and the U.K and these will continue through the afternoon becoming more westerly-orientated as we move towards dusk.  These showers will be pushed along by a strong to gale force westerly / north westerly wind and it’ll be a cool one for sure, so expect mid-teen temperatures today in that wind. Time to reach for the winter buff or snood I’d say (this one is my favourite :)….

Onto Tuesday and that low pressure system that has brought us unsettled conditions moves off north east and takes the majority of the rain with it, so a drier day is likely on Tuesday with most of the showers confined to the north west coastline of the U.K. We will still have that strong wind in place though so continuing to feel on the cool side if you’re out in the wind. Later on Tuesday as we approach the evening rush hour, we see another band of heavy rain push into the south and west of Ireland and this will quickly push north and eastwards so a wet end to the day here. Overnight this band of rain is likely to push into all areas so significant rainfall expected overnight into Wednesday.

So for Wednesday we still have the remainder of that heavy overnight rain affecting our weather with the heaviest rain reserved for the north of England up to The Borders of Scotland as we kick off mid-week. That doesn’t mean that everywhere else will stay dry though because we can expect rain across the north of Ireland and Scotland with another band pushing into The South West. Some of that northern rain may also push down into The Midlands. Later on in the day we will see another rain band push into Kerry unfortunately. Still with those strong westerly winds but they’ll lighten as we approach the evening and turn round to the north west. Staying cool then.

Onto Thursday and that wind change to north westerly / northerly means a cool day for all and continuing unsettled. There will be more in the way of sunshine around on Thursday between the showers that will rattle across the U.K and Ireland so a better drying day I suppose you could say (trying to be positive that is..). I don’t think we will see the same intensity or frequency of showers so for many Thursday could be a drier day. Staying cool mind with mid-teens the best you can hope for considering the direction of the air flow.

Closing out what will have seemed more like an October / November week, Friday sees high pressure nudge in from The Atlantic (See Mr Collins it will arrive but may be not to give an Indian Summer :( ) and that means a drier day is in prospect for all areas but that high will continue to hold the winds in a northerly orientation so it’ll remain cool, maybe even cooler for Friday with that wind direction but it should stay largely dry. I say largely dry because there’s a risk of a new rain front pushing into Donegal / Connacht later on Friday afternoon and if that comes to pass it’ll signal a wet end to the week for Ireland.

The forecast for the weekend will be a tricky one because this wet weather over Ireland has the potential to move eastwards on Saturday morning but exactly where that line will be drawn is difficult to say. So for Saturday we may see a very wet day for the west of the U.K and east of Ireland depending on where that line ends up being drawn. On this one I’d suggest you keep an eye on your forecasts for the end of the week but expect the Saturday rainfall prediction to change a lot. Sunday looks drier with lighter winds and all in all, a slightly nicer feel to the weather with a change to a more southerly / south westerly airflow and hopefully slightly better temperatures. It should remain dry with just the risk of rain across the north east and east I think..

Weather Outlook

So I knid of promised high pressure for next week didn’t I or at the very least hinted at it in last week’s blog well that’s what we’ll get, certainly for the start of the week anyway. So Monday should see us start largely dry and settled next week with a much warmer feel to the temperatures as that warm air pushes in from the west. Light winds so all in all a nice start to the week. It should be largely dry but there is a risk of some rain across the east of the U.K as the high / low battle line will be just off us in The North Sea. I think the west and south will be dry and warm and this should extend into Tuesday and Wednesday at the very least. The slight buggeration factor will be a northerly low pressure system that might introduce some rain across the north and west during the week but I don’t expect it to be heavy. So not exactly an Indian Summer but better weather next week, warmer and drier, still with the threat of some rain though but I think it won’t be a patch on this week and the winds should be lighter. As we progress to the end of the week we see Scotland and the north come under the influence of that low pressure so cooler and more unsettled here. The south and west should hang onto that warm high pressure though so a bit of a north / south divide on that front.

Agronomic Notes

Disease Pressure – What else ?

Yep it’s that scratched record again but on a serious note we had another extremely aggressive week of disease pressure last week especially across the south of the U.K so I thought I’d first have a look at some data to see why. Then I thought I’ll have a look at some other locations around the U.K and Ireland to see if everyone was in the same boat ?

Now before you say there’s no location near you, I have to say I simply don’t have the time to download, transpose and graph out multiple locations…well not yet anyway….but I try my best..

So starting off with a south of England location, Epsom in Surrey (these are chosen randomly)

0409100917DiseasePressureEpsom

So above is a chart of rainfall, temperature and humidity over the last week and what I’ve done is to highlight in a red dotted line the period of time when the humidity was > 90% and the air temperature greater than 15°C.

Now it doesn’t mean that outside of this you won’t be seeing disease, it means these conditions represent maximum disease activity / pressure and that’s for me the most important thing to look at particularly when we go on to discuss fungicide efficacy.

So we can see last week that there was a period starting on 6.18 a.m. on the 4th Sept through to 10.41 p.m. on the 5th Sept, when the humidity and temperature were conducive to high disease pressure, a total of 39 continuous hours. We then had a shorter period between 8.46 a.m. on the 8th Sept through to 7.41 p.m. on the 8th Sept, when again disease pressure was high, another 11 hours in total.

So last week we had 50 hours of high disease pressure, that’s over two days worth and that’s why we saw very aggressive Microdochium.

Aggressive to the extent that most fungicides were unable to limit the reproductive growth of the pathogen because we are dealing with the see saw of fungicide holding back pathogen population growth vs. climatical conditions promoting pathogen population growth.

Last week during these red dotted periods, the latter won.

Now probably the only fungicide that would work in these conditions is a local penetrant like Iprodione because not only is the A.I loading high (the amount you’re applying per hectare) but it also gets into the plant fast. (and you need both to control disease…)

Dovetail that in with the potential presence of contributory turf conditions in terms of surface organic matter levels holding water and promoting pathogen growth, susceptible plant species that most of us are dealing with, Poa annua, and the problem is a hard one to deal with and will become harder once we lose Iprodione.

So if you had aggressive disease activity on your turf last week, firstly you weren’t alone and secondly, you’re probably going to have to get used to it to a certain extent.

Let’s look at some other locations and a quick trip across The Irish Sea to Cork…

0409100917DiseasePressureCork

Not quite so bad here in terms of the longevity of continuous disease pressure but it was still present for 24hours at the start of the week and then another short but nasty blip for 4 hours on Sept 8th. So we have a total of 27 hours of disease pressure here last week.

Half that of the Southern England location though mind…

Up to a not-so-sunny Manchester and you can see again we have some aggressive disease activity, not to mention a lot of rainfall (no wonder you guys are fed up of it :( )

0409100917DiseasePressureManchester

So for Manchester we see a period of 24 hours between the 4th and 5th Sept when disease pressure was extremely high and just to make matters worse no chance to apply a fungicide, turf hardener, etc because of the near continuous, heavy rainfall on the 5th, 8th, 9th and 10th… In other words tricky conditions from a greenkeeping and indeed groundsman’s perspective because not only will this combination of temperature and humidity drive on Microdochium nivale, it will also promote Red Thread, Dollar Spot and Leaf Spot to name but 3 others…

Not to leave Scotland out, we head up country to South Glasgow…

0409100917DiseasePressureKilmarnock

A shorter period of high disease pressure here simply because this location was cooler so 12 hours of disease pressure here.

So hopefully you can see how variable the disease pressure picture is and in this case how severe the conditions were for The Midlands south to The South West and southern part of England.

Looking ahead

Now this week though unsettled will I think produce less disease pressure simply because we are cooler and we have a brisk wind which will reduce the humidity between the rain showers.

I’d love to hear your feedback on this at the end of the week maybe to see if this synposis is accurate.

That’s all for this week and hopefully a less bitchy one for us all :)

All the best…

Mark Hunt

 

4th September

170904_gfs_pres_500p_loop_eur

Hi All,

Well the first blog of September is upon us. Normally I see September as a bridging month between summer and autumn but I think this year that will be different because there’s no sign of the stabilising high pressure that tends to assert itself at this time of year and bring us an Indian Summer. Don’t get me wrong, it’s sitting out in The Atlantic but it looks like a succession of Atlantic low’s will keep it at bay for the moment :(

This week we will have another north – south divide in terms of the weather with low pressure affecting the north of the U.K and high pressure the south. Towards the end of the week the signs are that the low will drop south and we will experience our first Atlantic storm of the autumn.

Ok onto the weather synopsis for this week…

And it’s a quietish start to the week with Monday seeing a vestige of yesterday’s rain fronts moving away out into The Channel and The North Sea in the form of light rain over Wales, The Home Counties and the north of England. I did mention that it’ll be a north-south divide this week and already we can see rain into the west of Scotland, this will move west through the morning to bring rain to central and eastern areas as well. We also have another band of rain just approaching the west coast of Ireland and due to make landfall in Galway pretty soon. Across the south and east of the U.K, we have a muggy, misty start to the week with a low cloud base after overnight rain. It’s not all doom and gloom though as here we should see this cloud slowly thin to bring sunny intervals and probably the warmest day of the week with nice temperatures expected this afternoon. For the west of England and Wales, you’ll be the recepient of that cloud base from the west and so a dull day here with not alot of breaks in the sunshine at all. Ireland will see that rain lighten and cross country through the course of Monday and then clear from the west to leave a nice evening along the west coast of Munster. Scotland I’m afraid keeps that wet theme most of the day with the rain consolidating this afternoon to bring heavier rain to central areas. Temperature-wise, I think we may hit the low twenties later on this afternoon over The Midlands, a couple of degrees lower than that across the south and high teens for Ireland, Wales and Scotland. Winds will be southerly turning to south westerly and light initially. It will feel muggy in the south.

Onto Tuesday and here the feature of the day is a band of heavy rain that is due to cross south Munster and Leinster overnight and then push across Wales into north west England with some pretty heavy rain expected across North Wales and The Mersey area early doors, with this rain pushing east across northern England and towards The Humber by the morning rush hour. Through the morning this rain will clear the south of Ireland and push south into South Wales and The Midlands and southern England, lightening as it does so. By the afternoon this is gone and we finish here with some sunshine and warmer temperatures. After that early rain across the south and east, Ireland looks to dry up and leave a sunshine and pleasant day behind for the rest of Tuesday. Scotland looks to start dry but a band of rain affecting the west will push eastwards into Central Scotland by the afternoon bringing a wet one to this area before moving eastwards. The winds will freshen on Tuesday to moderate and be more south westerly / westerly. Temperatures will be slightly cooler with mid to high teens expected.

Wednesday and I think Thursday will be the driest days of the week south of the Pennines before low pressure comes in with a vengeance for the weekend. So make hay while the sun shines :) So Wednesday still sees rain over Scotland I’m afraid, a wet week for you guys for sure sad to say with rain mainly affecting the west of Scotland through the entire day. This same rain band will also affect the north west of England, from North Wales upwards through most of Wednesday. After a dull and cloudy start for Ireland, we see the clouds break and a nice, dry day for you beckons with some sunny intervals. The same is true for the east and south of England, really anywhere east of that rain across the north west and then south across The Midlands into Central England and including Wales. Temperature-wise it’ll depend on how much the clouds break but high teens and possibly into the twenties is likely here. Mid-teens for Ireland and Scotland I’m afraid with a light to moderate westerly wind expected.

Thursday sees a similar pattern except they’ll be less rain around with just the north west of Scotland likely to be affected. Elsewhere you can expect a very pleasant day with long spells of sunshine and broken cloud across Ireland, Wales and England. Although it’ll be a drier day for Scotland, you’ll keep a thick cloud base so a dull one here. As we approach the end of Thursday we will see the first effect of that deep Atlantic depression with a heavy rain front pushing into the north west of Ireland and Scotland late afternoon / dusk. So a wet end to Thursday here. Temperature and wind-wise, similar to Wednesday so pleasant where you see the sun.

Friday sees that heavy rain cross Ireland overnight to leave a much more unsettled feel to the weather for the end of the week. That rain will push into Scotland and then head south across northern England into The Midlands and finally the south of England in time for Friday morning’s rush hour. A much windier day on Friday as the low pressure exerts itself and this will be a feature for the weekend and perhaps beyond. So a sunshine and showers day for Ireland on Friday and after that initial rain pushes through we will see more rain primarily affecting the west and north west of Ireland and the U.K through Friday p.m. Once that rain has pushed through on Friday morning I see things brightening up thereafter for The Midlands and the south of England so not a wash out by any means.

9thSept

So onto the weekend and if the forecast holds, it’ll be a wild one though good for boogy boarding I’d say on western coasts ! :) The above shows Unisys’s projection and you can see how finely poised the weather is with warm, high pressure out in The Atlantic and a deep trough forming over the U.K, into which it is projected that this weekend’s and possibly more low pressure systems will slot.

Now I’ll add the forecasters caveat that I’ve seen this kind of forecast before and it can change with the low pressure shifting eastwards and the high following it. This time though I don’t think so, so I’m sticking to my guns in forecasting that this weekend will be windy and potentially wet as well with showers rattling in on a cool north westerly wind for Saturday. Sunday morning may see a brief respite in places with lighter winds but through the course of the afternoon, these will strengthen again and whip round to the north pushing temperatures down a little. There’s no point in adding rainfall detail on other than I think the north and west will bear the brunt of it,

Weather Outlook

So I think next week looks like starting unsettled with wet and windy conditions in place and that wind will be in the north / north west as we get squeezed between a high and low pressure. Tuesday may see a quieter, drier start but it won’t last as another low pressure is due to slip down into the trough and bring more unsettled, wetter weather for the second half of the week. With high and low pressure fighting it out, it looks like we will have northerly winds for a good part of next week so that means cooler for sure with mid-teens likely the order of the day. Any signs of hope around the corner ? Well there’s a possibility that high pressure may exert itself by the end of next week but that’s a long shot sitting at my desk here and now sipping a nice coffee and contemplating….

Agronomic Notes

Ok so since this is the first blog of September, we will look back at August and what one of my regular contributors called a sh***y month and yes Pete I wouldn’t disagree with you on that one…:(

The Oxfordshire – GDD Data

MonthlyGDD2017OX

So you can see in the above that August came in with a total monthly GDD of 314.5…That automatically marks it down as a cool one when you compare with last August when we hit 364.5 at the same location. We will delve down into the detail later in the blog…

Cumulatively for the year, this is how we look…

CumGDDTheOx2017

So despite having a cooler and we know wetter August, we are still on track to record the warmest year to date from a purely GDD basis. Interestingly 2014 is the current title holder and during that year we also had a wet and cool August following a very hot July because I remember Anthracnose was a real problem that year for many during August and September (the latter was very dry if I remember correctly)

UK – GDD Focus

Bit of a shortage of contributors this month but thanks for the data I did get and fortunately because I’m now able to access regional weather stations I’ve added some of my own locations of choice….

AugGDDRainfallUK

So here we can see that once again the south west of England was in the firing line for rainfall with our Devon location once again our wettest. Thereafter our London location came in 3rd highest of the rest of the U.K and that’s because the south east has a tendency to pick up continental rainfall which the rest of the U.K doesn’t always do. The west coast of Scotland, like Ireland is always going to be up there because if there’s an Atlantic low pressure system around, this area is normally in the firing line.

Ireland – GDD Focus

AugGDDRainfallIreland

So Ireland paints a similar picture geographically with the westerly and north westerly locations picking up the highest rainfall. GDD-wise the results are quite similar with Dublin the highest (just) being furthest away from rainfall and closer to the warmth of Continental Europe in more ways than one I’d say :)

Monthly Focus

So on balance why would we describe August as a crappy month from a turf managers perspective when it hasn’t been too hot and save for the west of Ireland, Scotland and The South West, (not wishing to be dismissive here)  it hasn’t been too wet with 50mm the average monthly rainfall ?

The first part of the answer is how the rainfall has fell with most locations showing that 50% of the monthly rainfall fell on just 3-4 days of the month and that provides us with a problem.

GPRainfallAugOke2017

GPRainfallAugCork2017

You can clearly see the peaks in rainfall above which represented 15mm + of daily rainfall occurring on a low number of days.  If we drilled down further it is also likely that during these high daily rainfall events, the actual rainfall rate in mm per hour probably exceeded 100mm per hour at some points in the day. This type of rainfall rate in mm / hour will quickly saturate a push up green, soil-based sportspitch, fairway, semi-rough, delete where applicable.

When it was wet it was also growing at close to maximum…

The reason why I produce these ‘stacked’ graphs with one parameter on top of another (you should try it sometime, it’s a real head scratcher to do…) is so you can see the relationship between the two across a set time interval.

So if you look above for both the Okehampton and Cork locations, you can clearly see periods of the month when the Growth Potential was close to 1.0, (most of it in the case of Okehampton) i.e optimum conditions for cool season grass growth and you should also be able to see that these periods coincided with rainfall.

So we have saturated or potentially saturated surfaces growing really quickly and needing cutting even more regularly than normal. Just getting the job done is hard enough resource-wise but maintaining good presentation as well without loads of clippings lying around is tricky to say the least. So that’s one of the reasons August was a bit of a pain from a growth management perspective, the other is unquestionably disease activity…

Temperature + moisture = high humidity = plant leaf wetness = disease

Dew

I know I have talked about this before so forgive the scratched record scenario but the reality is that leaf wetness promotes disease and the higher the humidity, the wetter the leaf surface. Just typing this now it’s really muggy outside and my weather station is saying we have been tracking at > 90% Relative Humdity since 10.12 p.m last night and currently we are still > 90% so that means 14 hours of high humidity coupled with an air temperature that hasn’t gone under 12ºC over the same period.

In other words ideal disease development weather.

Picking the Swansea location (about time I included South Wales in the weather stats), here is the data for August, 2017 and remember we are looking for > 90% humidity as a driver for disease…

MRHSwanseaAug2017

So we can see that for 19 days out of the 31 days in August the maximum humidity exceeded 90% and for 7 days it exceeded 95%.

These will have been the real driver days for disease development and that’s why you will have seen more Dollar Spot, Red Thread, Microdochium nivale and Leaf Spot (on sports pitches mainly but also some high ryegrass content rough) during this August compared to other years.

What is to be done going forward ?

The immediate problem for me is Microdochium nivale because if we look at the fact that we are carrying disease now in our swards into September and that the next 7-10 days (depending on your location) looks unsettled with further rainfall and high humidity, then it’s likely that this will continue into the middle of September at least.

The problem with this is that as daylight hours shorten, then grass growth levels will begin to drop back as temperature and particularly night temperatures drop.

If you look at the GDD information at the beginning of this part of the blog you can see the difference in monthly GDD totals between September and October. In a mild October we can lose 25-30% of our growth potential vs. September, in a cold October this can increase to 50%-60%. (look at 2016 as an example)

So the dynamic between growing out the disease as fast as it develops begins to change and we see a higher potential for the disease developing down into the crown of the grass plant and ultimately causing scarring. So that’s why I am a fan of trying to minimise the population of the disease before we reach October.

Easy to say, harder to do, with less effective, systemic  fungicides as the future option and the loss (at some point in time) of Iprodione, the job is and will get harder for sure. That’s why we have to work on all of the contributing factors to disease development wherever and whenever resources allow us to do this including dew removal, surface organic matter control and maximising plant health through this period.

Again easy for me to sit here and type this, but I appreciate with resources and specifically staff numbers difficult to keep at a constant (particularly through the holiday period) it’s no wonder we drop the ball on occasions. It sure is a big challenge as is maintaining surfaces with casting worms and increasing insect populations with the demise of control options – answers on a postcard on that one…:(

Sorry to be a bit doom and gloomy but it is a fact that the weather can make or break this game we are in and when it works against us, life can be tough for sure. During these periods it is essential to communicate to your team and management of the challenges we face and are facing and hopefully the data in this blog goes some way to help this process.

Ok I have a bitch of a week ahead (mostly of my own making) so it’s time to face up to it and get my own house in order.

All the best for the coming week….

Mark Hunt