So we are into September and generally it’s a quiet, settled month with high pressure traditionally dominating the scene before we give way to Atlantic lows and the start of autumn proper. Looking at this week and beyond I don’t think that’s going to be too far off the mark though it won’t be a long, dry one as we had in 2014….
If you didn’t catch the British MotoGP over the weekend, you missed a corker, (ITV4 Tonight 10pm) with our man Cal in the thick of it again and delivering another superb rostrum. 🙂 Compared to Formula Snore, it was a rivetting and brilliant spectacle.
Ok back to the day job, onto the weather and what lies in store for us this week and beyond ?
General Weather Situation
So Monday starts off pretty dreary for many with overnight rain across some areas of the U.K extending into the morning with some pretty heavy showers over Central and North East Scotland and Mid-Wales / Herefordshire / Worcestershire. As we go through the morning we will see a continuation of that rain along western coasts of the U.K, lighter rain inland as well whilst Ireland looks to be largely dry. As we progress through Monday afternoon the rain fizzles out over all areas to leave a settled evening with maybe some late sunshine as gaps in the cloud emerge. Lighter winds than of late from the south and high teens / low twenties the temperature. Muggy though with that humidity and cloud cover.
Overnight into Tuesday and we see a rain front push into Kerry and drift slowly across Ireland during the wee hours making landfall in the west of Scotland in time for the morning rush hour. Some of this rain, light though it is will drift down into north west England and North Wales. South and east of this we have a settled, dry day with some cloud cover that looks to hang around pretty much all of the day, with the exception of Eastern Scotland where you should see some nice sunshine. Continuing warm with temperatures building in the south to the low twenties maybe even the mid-twenties if the sun breaks through. High teens, maybe touching the twenties for the west and north and continuing humid especially in the south. Ireland could feel nice and toasty 🙂 A warm, muggy night to follow as well.
Moving onto Wednesday and still some light rain, mizzle about over Ireland, Wales, western coasts and Scotland first off on Wednesday morning but further south the sun will break through and temperatures will take a hike upwards very quickly. That cloud cover will break over Ireland and Wales as well but further north for The Borders and Scotland you’ll continue ot see light rain I’m afraid. For Wednesday afternoon we see the sun pushing through across the south of the U.K and up to around The Humber estuary and those temperatures may hit 25°C plus when it does. Cooler today for Scotland and Ireland though with high teens the order of the day as low pressure begins to have an effect. Winds continuing from the barmy south for the U.K though.
Onto Thursday and that low pressure extends its influence with the wind swinging round to the west and feeling much cooler than the previous days in the south of England. Scotland though will be the exception as warm winds funnel around that low and so here they may have a really warm, mid-twenties day with bright sunshine breaking through. For the reast of the U.K, a bright but cooler day with high teens / low twenties the order of the day and feeling a lot less muggy. The south east and east coast of England will hold onto that temperature though so mid-twenties here I think. Ireland looks to have a dull day, with light rain being closer to that low. During the afternoon expect more rain fronts, heavier in nature to push across Ireland and into south west / Central Scotland by Thursday evening. Remaining bright and sunny throughout further south with a moderate to strong westerly wind.
Closing out the week we have a north / south split with that low pressure rattling showers across Ireland, the north of England and Scotland. Some of this rain may be heavy for Ireland along south western and western coasts and through the afternoon I expect it to intensify over north west Scotland as well. Further south it’ll be dry and likely remaining windy with temperatures just nudging the twenties until the evening when I think rain will edge into the south west of England, Wales and western coastlines. Again I expect the south east and central England to remain dry and bright with warm temperatures.
Looking at the weekend we have that low pressure likely to put a spanner in the works of anyone hoping for constant sunshine 🙁 So Saturday sees that western rand band pushing slowly eastwards and bringing rain to most parts during the course of Saturday. Either side of it I’d expect it to brighten up and be pleasant with again the south east corner of England hanging onto the warmest, driest weather longest with that rain not likely to get to you till the evening. Even then it will have decreased in intensity. On the western side of this rain band it’ll feel fresher with temperatures in the mid to high teens with the heat hanging on in the east. It wouldn’t surprise me if we see some thunderstorms through Saturday as well as moist air meets warm, continental air. Sunday looks to stay unsettled over Ireland, north west England and Scotland but further south it’ll be the best day of the weekend with long spells of hazy sunshine and temperatures just touching the twenties.
Looking ahead to next week now and we start the week with a continuation of that north / south divide with low pressure affecting the north and west, so cooler, unsettled and windy here vs. a warmer, more settled picture for the central and southern half of the U.K. By the end of Tuesday I think high pressure will begin to dominate proceedings so warm, dry and settled everywhere and that’s the way it’s likely to stay I think until maybe the end of the week when I think a northerly low pressure may slip some further rain into the north and west.
First off let’s look at how we shaped up for August in our usual Thame location…
The top graph shows the total GDD for the month to be 364.5 which is the highest (just) that we’ve recorded since we started in 2010 and marks August as the hottest month for this location.
Looking at the Irish locations we see a pretty good consistent temperature month across all of Ireland and this was because the high pressure that influenced the weather was situated out in the Atlantic. Dublin and Valentia were the warmest locations in Ireland.
Ok nice graphs but what can we take from this data ?
PGR Application Frequency
Well if we look at PGR applications in terms of Trinexapac-ethyl and these monthly totals for GDD, we’d have to be on a fortnightly application interval to maintain regulation else there would be a good chance that the plant would come out of regulation, the so called ‘rebound effect’. In the warmer areas of the U.K, this interval would probably have to reduce to 10-12 days to maintain consistent regulation. As we’ve talked about before, TE breaks down faster in the plant during periods of warm / hot weather and so its longevity is compromised. This means you have to apply more frequently (but not at a higher rate note) in order to keep the plant regulated. You can find the research to support this here
Hot Temperature Stress
I mentioned last week that the high temperatures and E.T in August will have caused signifcant, if short-lived, plant stress. Was this same across all of the U.K and Ireland ?
We can look at this using Growth Potential Data…
So for this Surrey location we clearly see high temperature stress on the 24th and 25th August. Let’s compare it to our other locations…
So we can see markedly different rainfall patterns depending on the location, but no other chart shows high temperature stress bar the Surrey location.
So we can conclude from this that Anthracnose Foliar Blight and Dollar Spot which are diseases consistent with high temperature stress are likely to be more of an issue in the Central England because of the high temperatures noted here. This doesn’t however mean that other areas will have no Anthracnose because the other form of this disease, Basal Rot, prefers periods of leaf and soil wetness and you can see these are a feature of the Dublin and York locations with Bristol similarly affected because of the high rainfall earlier in the month.
We know that Anthracnose as a pathogen needs high temperature to initate spore germination, around 25°C it is said, so as I look at the temperature information received, these are the highest recorded air temperatures for the various locations ;
So you can see why Anthracnose Foliar Blight is likely to be more of an issue in the U.K compared to Ireland, but the wetter Irish climate will mean more likelihood of Anthracnose Basal Rot as the surface is wetter for longer. That would explain why frequent topdressing with high annual totals is a modus operandi In Ireland and the same should be true here in the U.K in wetter parts of the country.
I’ve got Anthracnose what should I do ?
First off there is no curative spray for this disease, it’s a bit like seeing a speed camera van, by the time you see it, it’s too late. (well with my driving nayway 🙁 )
Spraying a sward with active Anthracnose will ‘ring fence’ the affected plants but you’re still likely to see die-back on new plants because they were already infected and ‘going over’ before you sprayed, they just didn’t look like it at the time. Some products do kill the Anthracnose spore but again I don’t think this is foolproof as you tend to see Anthracnose re-occur on the same area or same greens the following year despite being sprayed.
We have to introduce new plants to the area soonest and for me that means over-sowing bentgrass into the affected areas or Fescue Bent if you prefer whilst we have temperature. Pre-chitting it in damp rootzone can speed up the process. Lightly aerating the affected area to punch holes through the surface organic matter and then introducing the seed once they’ve been topped up is another given. Maintain good nutrition to increase tillering / growth and I’d be dropping my PGR rate or even dropping it completely because you shouldn’t use a PGR on newly-emerging seedlings and it is these that you want to encourage.
I’d also look for factors that may have increased the incidence of Anthracnose on a particular area of green or green location. Thatch levels, rootzone characteristics, moisture levels, air flow are all likely to contribute.
Other diseases doing the rounds…
With mild temperatures and 87% humidity (it was over 93% early doors) then we can expect plenty of Red Thread, Superficial Fairy Ring, Microdochium and on sports pitches, Leaf Spot…..The fortunate aspect though is that with good temperatures this week and recent rainfall, we should be able to grow things out as fast as they come in without needing to resort to a fungicide spray. So I’d be keeping nutrition nice and balanced, no point in having a weak plant else it is just easy pickings for these type of diseases. You may also want to physcially grow out foliar diseases like Red Thread and for that reason I’d be careful of my TE rate over the next fortnight.
Nice week for spraying outfield…
With light winds for the first part of the week and recent moisture, this week is good for spraying outfields and particularly combining nutrition and selective herbicides to knock back ‘summer emerging’ weed species whilst they are growing well and uptake conditions are good…
Ok that’s it for this week, I’m off to do a chat in deepest darkest Lancashire this evening, I look forward to seeing everyone there 🙂
All the best..