September 19th

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Hi All,

You could say summer came to a very abrupt end on Friday with a huge and concentrated band of rain that pushed up country early in the morning. I was awoken to flashes of lightning and claps of thunder. As you can see from the ATD Lightning Archive nearly 10,000 seperate lightning strikes were recorded that day. As for rainfall, I’ve heard totals of 60mm in 2 hours in the south of England. Here in Leicestershire I recorded 43mm with 23mm falling in less than an hour. The band of rain here was intense but narrow, meaning you could drive 10 miles east or west of here and they recorded only 3mm ! (Lightweights!)

Lightning160916

I took some water samples in the middle of the storm (yes I know, definitely had the neighbour’s curtains twitching 🙂 so I’ll be reporting how much nitrogen was present in the rainfall next week. In the storms of the week before I measured 2.5kg / N / Hectare per inch of rain, which is higher than normal and due to lightning oxidising nitrogen dioxide in the atmosphere, forming nitrate nitrogen. So that’s why areas green up so rapidly after natural rain even though they’ve been irrigated.

Much fresher since this rain with a clear 10°C drop in air temperature from the highs of last week with Gravesend recording 34.4°C last Tuesday.

Talking of last Tuesday I was out applying trials in the heat and humidity when I noticed this weird cloud pattern as moist air from the west hit dry, hot air directly above me. You can see the line quite clearly and how rain clouds are being formed as the two meet.

front2 front

So was that the last of the summer ? Well probably not because I think I can see a return to warm, rather than hot days on the horizon, but not this week. Onto the matter in hand and a dull and mizzly week beckons….

General Weather Situation

So Monday starts the week dull and dreary really in most places with a weak band of rain stretching from the south west of England all the way up to north of The Humber. During the morning this rain will slowly sink south and east across The Midlands but it’ll fizzle out as it does so. Further north and west we should see some breaks in the clouds across The Borders, north of England and east of Ireland by lunchtime, but more cloud cover will form for the afternoon. By sunset that rain will be into East Anglia, light in nature though. Temperature-wise, nothing to shout about with 15 – 19°C from the west to the south and light north westerly winds in situ.

Looking ahead to Tuesday and we see the remnants of Monday’s rain still sitting over the east / south east of England so a dull and drizzly start to the day there. Further west and north follows a similar pattern to Monday with cloud cover at the start of the day breaking during the morning to give some sunny spells, particularly across Ireland, Scotland and the north of England. There is an exception to this rule of course and that’s the east of England around The Humber estuary which might see light rain come and go throughout the course of the afternoon / evening. Similar temperatures to Monday with the wind taking on a more easterly / north easterly aspect depending on your location.

For Wednesday we have rain pushing into the west of Ireland, west of Scotland and north west of England overnight accompanied by plenty of cloud cover. This rain will push inland into the north Midlands through the course of Wednesday morning and across Ireland. As it does so it will form a band stretching from Scotland all the way down to the south east of England by lunchtime. It won’t be a continuous band so they’ll be plenty of dry areas as well east and west of this rain. During the afternoon it slowly moves eastwards and fizzles out but there’s a chance you may end the day drizzly and dreary along the east and south east of England. Ireland looks to be pretty wet all day with that rain slow to move and hence slow to clear. You might as well come to Dromoland and listen to me harp on at one of the GCSAI’s Education Days 🙂  (That is if I manage to finish the talk today 🙁 Cue a twitchy Damian). The wind will have now moved round to the south on Wednesday so slightly milder in the south pushing up into the high teens but mid-teens under the rain in the north and west.

Overnight into Thursday that rain eventually clears the west coast of Ireland and pushes over Scotland overnight with another band moving across the south west of England and Midlands during the morning. By lunchtime this weak rain band should have cleared England but a new heavy rain front will already have made landfall across the west of ireland and be pushing inland. So a potentially wet afternoon with rain and heavy showers for Ireland on Thursday. For the U.K however we should be dry and with the cloud breaking a nice end to the day beckons before more rain pushes into the west of Scotland later on Thursday evening. Similar temperatures again with mid to high teens depending on your location and with a slightly brisker, south west wind.

Closing out the week we have that western rain pushing quickly across Scotland overnight to leave a dry start to many for Friday. Not that it will stay that way for long with rain pushing into Connacht and Donegal during the morning and heading north and east so expect it into the west of Scotland by Friday evenings rush hour. For the rest of the U.K, Friday looks to be a settled and dry day with hazy sunshine and a moderate to strong, south westerly winds. Mid to high teens continue to be the order of the day this week.

Looking ahead to the all important weekend and not great news for Ireland I’m afraid as some potentially heavy rain is projected to push into Kerry and head across the country during the day. By lunchtime that band of rain is set to make landfall across the west of the U.K so Scotland, the north west and Wales will bear the brunt of it I’m afraid though it’ll be lighter in nature by then. It’ll be windy with moderate to strong south westerly winds pushing this rain along. So an unsettled day for the west and north, drier for the remainder of the U.K but windy with it. Warmer though in that wind with temperatures pushing up towards the high teens where it is dry and mid teens under that rain. That rain pushes across Ireland over the course of Saturday and may set off some thunderstorms into Saturday evening / Sunday morning as it does so. Sunday looks to be drier across most areas with the possibility of some showers over Ireland early doors accompanied by claps of thunder and lightning. So a windy, cloudy day on Sunday with a slimmer chance of showers further south across England and Wales through the day, rattled along on a moderate to strong westerly wind. Temperatures similar to Saturday, mid to high teens.

Marathon

Our resident fitness freak at Headland Amenity, Mr Alex Hawkes, is running the Robin Hood Marathon this coming weekend along with his significantly better half who is doing the half marathon. He’s probably going to get up early and do a 40 mile cycle beforehand just to warm up whilst quoffing a quorn burger 🙂 (Can you tell I’m jealous)

He’s foolishly asked me for a forecast so Alex your day is likely to be dull with a strong westerly wind blowing down The Trent, but it should be dry with the chance of the cloud cover breaking just in time to glint off your finishing medals in the afternoon 🙂

A very genuine good luck to the both of you.

Weather Outlook

As hinted earlier, I don’t think we are finished with some warmth and sunny weather quite yet and that’s because next week is shaping up to be miles better than this one  🙂

So for Monday we look to have a much better weather picture with an Atlantic high pressure pushing in to bring warm and dry weather for most of the U.K and Ireland. There’s a really deep depression sitting north of us and because we are effectively sandwiched between the two it’ll mean we will have stong westerly winds particularly in the west and north. (which is good as they’ll be drying winds and you’ll need them after this week !) That low pressure will however bring some rain for the north, particularly Scotland accompanied by gale force winds and that rain may dip into England and Ireland on Tuesday though I think the south of England will miss it. By Wednesday we look warm and dry everywhere as those winds lighten but take on a more northerly orientation to leave a settled picture with high pressure in charge the rest of the week. So warm during the day and cool nights with some pretty heavy dews I reckon.

Agronomic Notes

A bit peaky and washed out…..

That isn’t a description of my general demeanour although at present it would be entirely accurate rather a comment on turf quality this week…

I’d expect turf to look a bit peaky after the sudden temperature drop and for some places, heavy rain of last Friday. When you get 30mm + of rain over a short period you can rest assured that it will have leached most of the available nutrient from the rootzone. Coupled with that we have a plant that was in water conservation mode up until Friday with high temperatures and high humidity and then overnight we go from the high twenties to low double figures. Of course that wasn’t the case everywhere I know, but for the bulk of the U.K, it was.

So it is hardly surprising that the grass plant is feeling a bit out of sorts this week and with a pretty dull week forecast for most, it won’t be receiving a nice tonic of U.V either. My advice would be to gently perk up the greens with a light foliar (if you have a spray window where you are) with more cool-temperature-available N (because it will be a cool week compared to last) than of late and definitely some iron and magnesium. When I say cool temperature nitrogen, I am meaning ammonium sulphate, potassium nitrate and not a lot of N because we have plenty of disease activity out there and we don’t want to encourage it.

Fertiliser and Disease…..

On that note it may be logical to state this but applying nutrient doesn’t directly encourage fungal growth in the case of the fertiliser types I’ve mentioned and Microdochium nivale (Fusarium to you and me but not Kate :)) I did some work recently on lab cultures of Microdochium nivale and none of the typical nitrogen forms we used stimulated growth of the fungus so they’re not directly utilising fertiliser as a food source despite some types of nutrient (urea and methylene urea for example) containing carbon, nitrogen and oxygen.

So when we hear that “fertiliser encourages disease” we must be clear that it isn’t the application of fertiliser itself more the physiological effect on the grass plant. That is to say applying high amounts of immediately-available nitrogen late in the season encourages soft growth with a succulent leaf and correspondingly thin cell wall. It is this thin cell wall and leaf succulence created by over-fertilisation that is the problem, not the fertiliser itself. Obvious I know but worth stating nonetheless.

On the flipside my work has also shown that certain forms of nutrient discourage the growth of Microdochium nivale (and other diseases) on the plant leaf presumably by changing the environment.

Last week was hot but it wasn’t a high E.T week…

So last week in some parts of the country we saw record temperatures with Gravesend (no wonder you always look thin Lee) hitting 34.4°C. So it was a hot and drying week then ?

Well no it wasn’t and that’s because we had high humidity typically touching 95% plus at night and > 85% during some of the days. When the air is full of moisture during high humidity periods it isn’t possible for more moisture to be evaporated off the grass plant or the soil so areas don’t dry out as you might first suspect they would.

Moisturemeter

That’s where moisture meters really pay their way because rather than reacting to the high temperature by irrigating, you can see clearly how the rootzone is retaining moisture and not drying out and cut your irrigation accordingly. Experience shows a drier leaf is less likely to develop disease.

Pearlwort

Pearlwort

I’ve been noticing for some while now patches of Pearlwort in fine turf and I think it is a consequence of last winters very mild and very wet weather and also this June’s wet weather as well. Pearlwort likes a wet surface so it serves as a useful indicator that water may be being retained in excessive organic matter (thatch) on a particular green or area of green. It is sometimes hard to differentiate between a patch of perennial Poa and a patch of Pearlwort so if you’re struggling, take a plug from the area and let it grow up on the window sill. You’ll soon notice the different leaf structure and flower buds as well. It’s even harder when you have Pearlwort growing through Poa so growing on a plug is a good way of confirming your hunch. Just to throw a spanner in the works of the wet surface and Pearlwort link, I’ve also seen it on a new sand rootzone which is definitely not sitting wet so it may be like Silver Thread Moss, i.e. a good competitor in very wet and very dry conditions (when grass cover thins)

Worms and Daddy’s

A lot of worm activity out there now after the recent high rainfall. This is a problem we are going to have to think about seriously now if the predicted revocation of Carbendazim does occur at some point next year (Saying that it’s had more combacks than Status Quo so you never know)

Mirror

Had to chortle at the recent Mirror Headline claiming the likely invasion of 200 Billion Giant Daddy Long Legs is imminent. Obviously penned by someone in London who doesn’t know the difference between a Crane Fly and a House Spider. I suppose the give away should have been the number of legs and absence of wings !!!! 🙂

On a more serious note with the first year of no Chlorpyrifos on amenity turf and the withdrawal of the same active from agriculture, we are likely to see a steadily increasing threat from Leatherjackets (and Chafers for that matter because of the disappearance of Merit) through this autumn and winter and leading into next year. I’m aware some companies are hawking around an agricultural insecticide, but just be aware of the label restrictions in terms of pest treated, buffer zones and re-entry into a treated area before you commit on this one.

I think we will see more CraneFlies around this autumn but it’ll be next spring before we really begin to ramp up populations of the larvae and that may bring us problems during spring aeration I’m afraid to say.

Disease Activity

Lot’s of disease came out of the woodwork last week with the heat, humidity and rainfall with Superficial Fairy Ring, Microdochium nivale and Red Thread top of my pile. It’s getting pretty close to applying the first Microdochium fungicide application of the autumn season now (though Ireland and Scotland will always be earlier because of their wetter climate) so my advice would be to apply a full rate systemic and include half-rate contact if you have signs of active disease.

To my mind, there is simply no point in half-rating a systemic fungicide because if you apply half the active substance you’ll get half the longevity of response and efficacy. It is vitally important (and will become even more important in the future) that we minimise Microdochium nivale populations during the coming 8 weeks because if that can be achieved, experience shows us that you’ll have less likelihood of re-occurrence during the winter. If you allow a high disease population to establish now and / or during October / November then you’ll be on the back foot all through the winter with the now common flare ups around old scars whenever we go mild in December and January (and the chances are we will go mild then)

Easy for me to type, harder for you to put into practice with the diminishing number of effective Microdochium fungicides we now have available. Let’s hope by the time the most effective fungicides use-up period is over, we have some new actives to replace them. Fingers crossed.

Ok that’s all for this week, got to finish my talk else they’ll be an embarrassing silence tomorrow in Westmanstown and on Wednesday in Dromoland  and Damian won’t be happy 🙁

All the best.

Mark Hunt

 

 

 

2 thoughts on “September 19th

  1. Graeme Taylor

    Pearlwort has been a major problem here on St Andrews New and Jubilee this year. It has been dry and moistures have routinely been kept at 10 – 15% in the top 2inches. OM levels sub 4% in top 20mm.

    A hit with relay turf, followed by a double scarify and feed with 8.0.0 @ 30g/sqm sorted it right out…

    Reply
    1. mark.hunt Post author

      Hi Graeme,

      It’s interesting that it looks to be symptomatic of not only wet playing surfaces but dry ones as well.
      This was news to me until last week when I was spraying a Cabadex trial on bentgrass (because you have to be careful with selectives and bent) and I noted it on a very dry rootzone. Probably similar to Silver Thread Moss in that it is a very good adpatative species.
      Thanks for the feedback.

      Mark

      Reply

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