November 9th

Hi All,

It was my birthday over the weekend, bit strange in a lockdown period but there you are…..

Received a very apt mug (Cheers Sim) which sums up my demeanour on most mornings….Sadly my garden is bereft of Hedgehogs after the Badger culled most of the community Hedgepigs in the spring and then the last two remaining died over the summer. I think they went into hibernation knowing a predator was about and never came out. Sad for me after all the effort I’ve put in to encourage them but hopefully sometime in the future they’ll re-appear.

A strange weekend weather-wise as we went from cold, bright and frosty to no wind, mild and dewy over the course of Saturday and that situation remains today as I type this.

So that’s 24 hours + of constant leaf wetness, high humidity and mild temperatures > 12°C.

Need I say more…???

General Weather Situation

You can see our problem in the GFS output above. Warm, southerly winds pushing up from Africa with an Atlantic low pressure approaching. Fortunately as we know when a low meets a high it generates wind as the isobars get squeezed in-between so that’ll put a stop to the current low winds, no E.T and a wet plant leaf. The question is when ?

So on Monday we have a low pressure system pushing bands of rain northwards across the south of Ireland, south west of England and across Merseyside. It’s not all gloomy mist, my colleague Dave reports that Cumbria looks beautiful this morning !. As we go through the morning that rain consolidates across the south of Ireland, The South West and across South Wales. Some showers will also make it inland to The Midlands as well. The winds however will remain light, maybe picking up a bit across Ireland but otherwise they’ll remain light and that will continue our disease pressure problem, more on that later. So gloomy on the whole, there will be some breaks in the cloud across the the north of England and Scotland. Enjoy them because there won’t be much sunshine around this week ! Temperature-wise we remain trapped in this muggy temperature band across the south of England, Wales so expect mid-teens during the day and a little lower at night. Ireland and Scotland will be a little lower but still 12-13°C day and night 🙁

Onto Tuesday and we start to see that change in the weather across the west as low pressure edges ever never to Ireland. Not quite there yet on Tuesday so we will endure another muggy, gloomy day with some rain pushing up from the south across the south coast / south east and England. We may also see some showers across South Wales pushing northwards along the north west coast of the U.K into the west of Scotland. So some rain around but most areas will stay dry on Tuesday with continuing light winds across the U.K, though they’ll freshen later across Ireland. Remaining mild though temperatures will be a degree or two down on Monday’s highs so 12-13°C the norm. Cooler at night though as temperatures dip into single figures for the first time since Friday night.

Wednesday sees that low pressure finally making landfall across Ireland overnight with rain, some of it heavy pushing in from the west across most of Ireland in time for the M50 rush hour (or not as the case may be). We will start to fell the effect of this low pressure on Wednesday with freshening south westerly winds from first thing so this will give us a break from a disease pressure perspective. During the morning this band of rain intensifies over Ireland and being slow moving it’ll lead to some pretty hefty rainfall totals and localised flooding I’d guess. Some of this rain will make it into the west, north west and central areas of Scotland during the morning but Wales and England look to stay reasonably dry a.m. By dusk that rain band makes it onto the west coast of the U.K and as we move into Wednesday night it slowly progresses eastwards clearing the west of Ireland as it does so. Some of the rain will be particularly heavy across Wales, the north west of England and west Scotland. Windier on Wednesday with strong westerly / south westerly winds.

Onto Thursday and overnight that rain band clears the U.K to give a fresher, sunnier start to the day, especially across Ireland and the west. A strong to moderate westerly / north westerly wind though will have temperatures struggling into double figures but I’d prefer that to muggy and misty. Ireland starts dry but with cloud building from the west as another band of rain threatens to push in from The Atlantic. This looks to make landfall across the west coast of Ireland around lunchtime Thursday and then edge slowly eastwards meaning heavy rain for the west, particularly across Clare and Connacht I reckon. Dry for Wales and England but that Irish rain will push into the west / north west of Scotland during Thursday afternoon. Winds will vary from westerly to north westerly and that’ll keep the temperature down to 9-10°C through Thursday.

Overnight into Friday and that rain pushes into the west of the U.K on strengthening westerly winds bringing some heavy localised rainfall especially across Wales, Cumbria and the west of Scotland. By dawn that rain has crossed the U.K breaking down into sunshine and showers across central areas but still heavy across western coasts. Ireland looks to start reasonably dry. With strengthening south westerly winds, the remaining rain showers move north and east across Northern Ireland and north west Scotland. So a breezy, milder day on Friday with some sunshine and a strong south westerly wind that moderates as we go through the day. Temperature-wise, expect 11-13°C for England and Wales, 8-10°C for Ireland and Scotland with some showers over the latter pegging back the temperatures.

The outlook for the weekend looks mixed.

Saturday looks pretty wet across Ireland and the west of the U.K later with strong south westerly winds pushing rain into Wales, the north west of England and west of Scotland later. Some of this rain will move inland through the course of Saturday afternoon. Overnight into Sunday this rain pushes eastwards across all areas of the U.K, clearing Ireland as it does so. So Sunday looks like sunshine and showers with some heavier rain later across Ireland and the west of the U.K. Breezy with south westerly winds so staying on the mild side with temperatures in the low teens for most places, maybe pushing mid-teens down south. Later we may see some heavier rain over the south coast / south east of England.

Weather Outlook

So as you can see from next Monday’s projected GPS outlook we are in for some unsettled weather next week with strong winds indicated by the closely packed isobars.

So next week looks like starting off mild, windy and with some showers although these look to be confined to the north and west because of the south westerly wind direction. As we go through Tuesday we see heavy rain across Ireland push north and east into north west England and Scotland whereas south of the Pennines looks to remain dry, mild and breezy. Wednesday sees rain further south across The South West and pushing north and east across central areas / Wales through the morning before more consolidated rain moves into Ireland later on Wednesday. During Thursday we see a change as high pressure tries to push in from The Atlantic which will cause the wind to turn north west so cooling off the temperatures and pushing rain further south on Thursday across most parts of the U.K., though Ireland looks dry. Still some rain around on Thursday / Friday for Scotland but as we end the week high pressure looks in charge so cooler, settled weather with lighter winds and fog / frost likely. That pattern could continue into the weekend.

Agronomic Notes

I’ve used this picture before but it is very apt given the weather we have had over the 2nd part of the weekend and the start of this week.

I see a lot of discussion about dew control products, their efficacy, longevity and like and to me it is very interesting.

There are basically two ways for a dew dispersal to work. Either the surfactant chemistry binds to the leaf and repels water thereafter or it sits on the leaf, repels water whilst it is in situ until it is washed off by rainfall. Now the products that bind to the leaf will obviously last longer and their longevity is principally dictated by removal by cutting and / or new growth / leaf coming through that isn’t covered by the first application.

There is always then the question regarding application of other materials be that fungicides, irons, hardeners, e.t.c before or after a dew control product, particularly if it is the type that binds to the leaf. The concern being that some of the leaf surface area is coated in the surfactant and therefore it may obstruct entry into the plant or more likely, it may repel the applied spray solution and wash it off into the soil. My advice for what’s its worth is always to apply what you want to go into or onto the leaf before you apply your dew control product and typically I like to see 5 days between applications.

I won’t go into companies or brand names because that’s not what this blog is about. What I would say though is that an application of a dew control product prior to say, this weekend will be worth its weight in gold in terms of reducing both the severity and longevity of plant leaf wetness and therefore disease.

Take a look at the leaf wetness vs. humidity vs. air temperature data from two locations in the U.K below.

You can see the very rapid transition from Saturday to Sunday when humidity and air temperature increased overnight and plant leaf wetness likewise. (highlighted in yellow)

The period highlighted in the yellow box is when conditions would be so in favour of Microdochium nivale development.

During this period we saw plant leaf wetness > 10/15 (which means in practice a wet leaf).

The combined period of plant leaf wetness was between 24-26hrs over the course of Saturday night into Sunday and through Sunday night into Monday morning. You can see both leaf moisture sensor readings dropped to 3 (out of 15) at 10 a.m. this morning as they picked up a bit of breeze, some sunshine and warmth enough to dry down the leaf. Now a lot of golf courses are in lockdown and / or with furloughed staff with many not having enough resource to send staff in at the weekend. Even if you did have staff in on Sunday morning at say 07:00, the dew was still reforming until midday. After that there was a brief period of dry down before it began to reform again at 16:00 and then the plant leaf stayed wet until 10:00 a.m. the following morning, with 12 hours of consistent maximum plant leaf wetness. Dovetail that in with an air temperature always in double figures and you have the perfect recipe for Microdochium nivale.

This situation is precisely when a dew control product application pays dividends and in practice even if it only lasts a week it will have massively reduced disease levels and perhaps saved a fungicide application.

So if you are seeing Microdochium nivale on tees, approaches, surrounds, fairways currently, the above is the reason why. If you’re seeing it on greens then it either means you aren’t sufficiently protected (maybe your last protective product has grown out in the mild conditions of the previous week ?) or the rate of pathogenic fungal population growth is exceeding the rate of fungal population control due to the above favourable climatic conditions. So in other words the balance has tipped very much in favour of the pathogen and looking at the forecast it will remain so across the south of the U.K, Wales, etc till Wednesday when the wind strength increases and we see quicker dry down of the plant leaf. For Ireland and Scotland, you’ll see it sooner than that because the low pressure will push windier, wetter weather from later on Monday / Tuesday.

Soil temperature dynamics

In last week’s blog I spoke about the rapidly increasing soil temperature on a high % sand-based construction with the arrival of mild air temperature and rainfall. Since then we have had some cold nights and ground frost but we are going to see that pattern repeat again over the next 7-10 days. So if you are in lockdown, have no golfers but you have plenty of signs of wear from increased golf traffic during the summer and autumn, I wouldn’t hesitate to run out an overseeder as soon as convenient to take advantage of the higher-then-normal (?) soil temperatures. I don’t believe you’ll lose the seed even if it went really cold (not that I can see that happening any time soon). A few years back I remember my local council cleared an area and threw ryegrass seed down the week before Christmas in the frost. I remarked to my other half that they were chancing it a bit on that front. By the spring they had great germination and a headstart to ground cover. Lesson learnt.

Now ground conditions, resource, budget, e.t.c might not be favourable, I 100% accept that, as always it is a suggestion / observation on my front.

OK, that’s me for another week, all the best to you all, stay safe and enjoy the March-time temperatures even though it’s November and only 6 weeks to the shortest day !

Mark Hunt