Not the nicest picture of Wells next the sea in North Norfolk where I spent some lovely time last week, but an apt one. You can see a front of ‘Haar’ (low cloud pushing in off The North Sea) in the background and the sea is relatively quiet at the height of a big spring tide. We have had plenty of muggy Haar days of late…..
I was looking for some Sea Bass chasing fry but the Milkweed is in which means poor water colour. Nevertheless I did manage to catch a lovely 6lb + Bass on a fly I tied myself which modesty prevents me from posting on this blog. OK, I’m not that modest so here is a pic just to prove it….The hat says it all 🙂 Some lads shore fishing close by thought it was a Cod and were horrified when I returned it to see another day. They were going to mug it off me they laughingly told me afterwards with more than a hint of seriousness when I met them in the car park later. Turned out they were from Leicester….enough said 🙂
The current weather system we have sitting over us is providing a lot of atmospheric moisture in one form or another, some heavy rain, heavy dews and high humidity. It is a far cry from the record heat they are recording over north west America and Canada currently with temperatures exceeding 45 °C outside and over 30°C in peoples homes.
This heat is caused by a peak in the jet stream and predictably the Daily Express has it ‘coming our way’…..They may have a point though because if you look at the maps for the Western Hemisphere, Europe is surrounded by heat on all sides with a strong heat front out in the Atlantic. Currently this is being held off by low pressure over the continent and south west of us, but if that dips out then we will see some significant heat this summer.
So if you’re swearing at the rain and low clouds and praying for some sunshine and heat, maybe you should be careful what you wish for….????
Back in the real world, I sat on our research plots yesterday and it was 18.5 °C, constant drizzle, 97% humidity and clouds to the ground. I reckon I could see at least 5 turf diseases which is kind of nice for a research plot as I’m sure it will replicate a lot of turf surfaces out there currently. (which after all is what you want a research plot to do 🙂 )
Pretty much everything is going to be on the move pathogen-wise so let’s see if the weather coming up this week and next is going to make our job easier or harder ?
Before I start this blog and as someone who isn’t a follower of football I must say ‘Cracking job Switzerland and Denmark of course’ (sorry Wales).
Looks like I’ll have the reservoir to myself tonight, anything to avoid another dull as dishwater England game accompanied by a thick book of excuses and historic rhetoric from many years ago….My English half wishes them well but someone needs to tell them which half the opposition’s goal is situated in else I don’t fancy their chances.
Onto the weather…
General Weather Situation
So for Tuesday we already have a continuation of that cool, wet, high humidity weather over the southern half of the U.K. You can clearly see the culprit, a Bay of Biscay low pressure system that is pulling moist and cool air off the continent on a north easterly wind. So already for Tuesday we have a raft of showers coming in off The North Sea to affect the southern half of the U.K. Head a bit north and west though and it’s a different story with much better weather for Ireland and Scotland with plenty of sunshine and temperatures north of 20°C. The demarcation point is sort of north of The Humber / York. During the day these showers will fizzle out and that cloud will break to give a nice day for the west and north of the U.K, a very pleasant one for Ireland with sunshine and no sign of rain. Further south we have that cloud mass coming in off The North Sea so a duller affair for the southern half of the U.K with plenty of cloud cover and temperatures in the high teens.
Overnight into Wednesday and we have a better day in store for the southern half of the U.K, once the cloud begins to burn off and retreat towards the east coast. So dull for a time before the sunshine breaks through away from the east coast to give some warmth and a bit of dry down after the saturated atmosphere of late. A continuing dry and warm theme for Scotland and Ireland with the former showing temperatures into the mid-twenties, high teens and low twenties for the former. Dry then for pretty much all of the U.K & Ireland until tea time when we may see some showers crop up across The South West and South Wales (bless them). So a bit warmer on Wednesday, up to and into the low twenties for the southern half of the U.K, Ireland and Wales, with Scotland a couple of degrees higher.
Thursday sees an almost carbon copy of a day to Wednesday with early cloud cover burning off and retreating towards the coasts to give long sunny spells and rising temperatures in the south into the low twenties, similar to Scotland again. Ireland may pick up a bit more cloud cover and that’ll cap off the temperatures towards the high teens and maybe later in the afternoon you’ll see some showers popping up over Cork, Wexford and South Leinster.
Closing out the week on Friday and again a very similar day to Wednesday and Thursday. Early cloud giving way to plenty of sunshine with the cloud layer retreating to the coasts. Similar temperatures to Thursday for Ireland, Scotland, Wales and England so all is fine and dandy for the close of the week. Out in The Atlantic though a rain front is pushing in courtesy of an Atlantic low pressure system and this will affect our weather for the weekend.
So this weekend will have a distinctly unsettled, muggy at times, warm and wet feel to it. We have a low pressure pushing rain into Ireland and the south west of England, Wales on Saturday morning and this will push north and east during the course of Saturday so if you start dry, you are unlikely to end it that way. Plenty of rain for Ireland, England and Wales but Scotland will stay driest longest as the rain is pushing up from the south. Winds will be from the south west and temperatures will remain high teens to low twenties despite the rain so that’ll tell you something about disease pressure which I’ll come onto shortly. Sunday starts drier but rain showers will develop through the morning consolidating into longer spells of rain by the afternoon and this time it’ll extend all the way up to Scotland. Remaining warm and muggy with a moderate southerly wind.
First up if you look at the GFS output above you’ll notice something that I’ve never seen before in 11 years of interpreting GFS output. The colour purple which I’m taking represents extreme heat (must be 50°C if you look at the Canadian output !!). Let’s hope it stays firmly in place over Africa because we don’t want that here thanks. Anyway I digress….
So next week as you can see starts with that low pressure still over us and a raft of cool moist air extending in from The Atlantic . That low looks set to dictate next week’s weather with plenty of rain for Monday, a short interlude on Tuesday morning before more rain pushes in during Tuesday afternoon across Ireland from the south west and heads north east. This rain pushes into Scotland on Thursday and we end the week wet and unsettled. High pressure then tries to push this low aside so things may get a bit warmer and less unsettled for the weekend after next but after that it is ‘delicately balanced’.
Well there’s a very clear tone to the agronomic part of this blog this week and it relates to disease pressure. Now it seems strange to be talking about Microdochium nivale pressure going into July, maybe not so strange for Ireland and Scotland which ‘tend to have’ some of the highest disease pressure in the summer months as they ‘tend to be’ cooler and wetter than Wales and England. ‘Tend to be’ is a dangerous term to use anywhere at the moment because of course both Scotland and Ireland are warmer and drier than Wales and England, so I may ‘tend to be’ wrong on this assertion.
Whatever, with high day and night temperatures, high humidity and extended periods of plant leaf wetness, we can be sure that just about every pathogenic fungus known to the turfgrass manager is having a field day at present. Just look at our Microdochium nivale algorithms for the last two weeks in 3 locations (sorry Scotland I don’t have a Scottish location supplying validation data as we speak)
With the low pressure systems being mostly Bay of Biscay-orientated, it is the south of England, south east and east of England that has very much been in the disease pressure firing line over the last 2 weeks. I can’t remember seeing such aggressive peaks before at this time of year and for sure it isn’t just graphical data. I have had plenty of fiery Microdochium pictures arriving into my phone via selected media channels over the last few weeks, so prediction and actual are pretty much spot on.
Now OK, I accept there’s been plenty of growth as well to mitigate fungal growth in the case of foliar pathogens like Microdochium, Dollar Spot and Red Thread but it doesn’t totally negate its effect.
Below is the Growth Potential for our research facility at Throws Farm, Great Dunmow, Essex for June 2021 ;
So you can see we have had optimum growth to counteract the disease pressure….
Now for me applying a fungicide to try and counteract this type of disease pressure is not pure folly, but it is close, because even some of the older, more effective chemistries wouldn’t stop this level of disease pressure. Having a systemic down before it will reduce those peaks for sure and maybe to the point where you see minimal disease ingression, but applying to active disease now, I don’t think you’ll get a great result until the climatic drivers that are creating this type of pressure subside. And then there’s the longevity when we have this level of current G.P across the U.K & Ireland. 7-10 days for a systemic @ £€’s per ha ?????
When will this current spell of disease pressure abate ?
Well I can see this sort of pressure continuing through till the end of next week before it begins to drop off…..
Got sent the picture above a good while ago from a cricket outfield and in it you can see some aggressive Fairy Rings and Red Thread. Both of these diseases love humid weather and especially when we have localised downpours and then high temperatures and humidity. I’ve had a lot of reports of Superficial Fairy Rings as well.
If they’re bad enough to consider treatment, I have had some success combining a good quality surfactant like…ha ha nearly had you….with Azoxystrobin. As we have talked about before, key is to locate the depth of the active fungi by taking a core from the ring, laying it on its side and dropping water down the profile till beading is evident.
In the photo below, we were dealing with Superficial Fairy Ring which was active right in the surface fibre so in this case you didn’t want to drench the mix too deep into the profile.
If it is deeper down in the profile, think about aerating before application and applying enough water afterwards to drench the fungicide down into the zone it needs to be in order to do its job. Bearing in mind we are talking either in the surface organic matter zone or below it, you need to use a surfactant that is effective at pulling water (and fungicide) into the hydrophobic organic matter, not all are. Again do a droplet test with your surfactant and see how effective it is at doing this.
I haven’t been sent pictures of Anthracnose yet but I’ve seen some turf symptoms that may be down to this pathogen although sometimes it’s easy to confuse them with plant parasitic nematode species like Spiral Nematodes (which can also cause yellowing of the basal leaf). Sometimes you are unlucky and have a complex of both, one a primary pathogen, the other a secondary. Isn’t turf interesting ?
So as hinted above I think we just have to tough this period out, keep the plant healthy, mitigate stress (your own and the plant’s that is :)) and don’t do something that will put the plant on the back foot and open the door to disease. (over-regulate for example on fine turf surfaces)
Hang tight and all the best..